Module 3: Secondary science - Physics: Look as a single side (2024)

Introduction

At the end of the doctrine of a subject, teachers usually did a test or exam to find out what their students have learned.Leave to help students.A good teacher will find out what students understand when they go together and which students find difficult and help them make progress.

This device has three short activities that fit into your normal educationProperties of contentAnd will show you how you are what your students understand.them in teaching other topics.

Interrogate

Good interrogation is really important and is not as easy as it can first look.Think.Good questions can promote thinking, encourage research and help with the assessment.

By thinking closely about the kind of questions you can ask you, your education will improve.

It is useful to come up with questions such as 'open' or 'closed' and 'person' or 'subject -centered'.

Closed questionsHave a single correct answer.They can reassure students and help you discover what they remember.

Open questionsDo not have a good answer or more correct answers.

Topics-centered questionsAsk things like "What's going on in a plant?" And "What kind of rock is this?"

Person centeredQuestions focus on the student and are less threatening and more student -friendly: "What do you think the plant goes in?" "What do you notice about the rock?"

A selection of teachers who were chairman of Benjamin Bloom came up with a taxonomy of species in which they identified 'Questions about lower order 'In 'Questions with higher order '.

It is important that youplanCorrect your questions.For example, when creating a practical demonstration or introducing a new item, you write a list of a lower order and a few questions with a higher order.Teaching, practice!You also have to think about how you can answer your students' answers.Try to give them time to think, ask more students the same question or let them discuss the answer before you answer.

Conventionally, students are asked to set up their hands when they answer a question.doesn'tTo ask them to set their hand.All will have to listen as they know they can be asked.Successfully answer some of your questions, they become more confident.

Cornflour and water - a curious mix!

Your students are probably familiar with the properties of solids, liquids and gases.or other of the categories.But what happens if this is not the case?Hand would meet all the criteria for a solid.

So some substances are absolutely difficult to classify.Is made of water and cornflour.

• A box of cornflour, 450 g (16 oz) or equivalent (a powder with a high starch content)
• A big mixing bowl
• A jug of water
• A spoon
• A large plastic food bag
• Newspaper or equivalent to treating the floor
• Water
• Dietary
• A cup or cup.

Method

• Pour¹/₄of the box (about 100 g, 4 oz) cornflour in the mixing bowl and add slowly¹/₂cup of water.
• Continue to add cornflour and water in small quantities until you get a mixture with the consistency of honey.Cups of water.As a general rule you look for a mixture of approximately 10 parts of cornflour to 1 part of water.
• Zinc your hand in the bowl of corn keeper and water and pay attention to the unusual consistency.Round, the more a solid, the mixture becomes.Sink your whole hand and try to grab and pull the liquid.
• Let go of a small object in the corn position mixture and then try to get it.
• Relax the surface of the mixture.If you have used exactly the right proportions, it will not spray anywhere.

To explain the properties of corn position 'Quicksand'

Maïzena Mixed with water is an example of oneHeterogeneous mixtureIt's a bit of a mouthful!So do not pour a remaining mixture into a sink - the water will evaporate and leave a massive lump of fabric that blocks it.

In fact, cornflour and water mixture sometimes function as a solid and a liquid at other times.the liquid) .

When you throw the surface with your hand, force the long starch molecules closer together.flows again.

If you push your finger slowly into the mixture, it easily goes in and feels like a liquid.

All liquids have known a characteristic asViscosity- or resistance to current.Jo more resistance to allow a liquid to flow, the greater the viscosity;For example honey.Viscosity less than for cold honey.Cornstarch, Water Mixtures and Fastzand consideredNon-setliquids because their viscosions change when a force is exerted,doesn'tWhen heat is applied.

Basic properties of content

Some examples of materials that are more difficult to classify

Some materials seem to be a single fabric, but are not:

• Sand (or powders, such as flower).These flows (like a liquid), but is made of small solids.
• Modeling of clay (eg 'plasticin') is a mixture of a solid and a liquid.
• A cloud flows into the air (like a gas), but consists of many small drops of water in the air.
• A jelly is a mixture where small amounts of liquid are mixed in another material that is a solid.
• Toothpaste is a mixture where small amounts of solid are mixed in another material that is a liquid.
• A foam is a mixture where a gas is mixed in another material that is a liquid.
• A sponge is a solid with air or liquid that is mixed with it.
• Some liquids (such as tomato ketchup) are thick and do not flow very well, but if you shake them, they become thinner and light light.

Set statements about solids, liquids and gases

Answer to teachers

Solid: 1, 5, 7, 11

Liquid: 3, 4, 8, 10, 14, 15

Gas: 2, 6, 9, 12, 13, 15

Student

Having students write about their ideas is a great way to find out what they understand.Your students do the opportunities for them to show what they know and be creative.

Writing in science should certainly not be limited to answering questions and copying notes.There are different ways in which you can use writing children to investigate their understanding, to develop their knowledge, motivate and refine their skills.

blowj*b

This stands forRelated activities relatedUnpleasantThe text.

A common approach is to give some text those words miss.A little easier.

Other approaches are as follows:

• Sentations that connect to each other to explain a process or phenomenon can be vocal and students must decide their correct order.
• Say that must be completed to give full definitions.
• Diagrams are delivered when students have to feel.
• A table is provided with a few holes that must be filled in.
• There is a piece of text where students must emphasize keywords or definitions.
• A piece of text is delivered and students need to make a table or diagram or to produce a summary.

Ord -matching

You give a list of scientific words and definitions.Students must match the right word with the right definition.

Write experiment on

By encouraging your students to write about their experiments in their own words, you show how much they understand.

Draft card or thought card construction

This includes breaking a complex idea or process, to sections and they graphically confirm to show their logical consecutive circ*mstances and how they contribute to a concept of the whole.The subject if the cards are useful.

Writing to another audience

This type of writing sometimes helps students to find science hard to find, but who enjoy the humanities.Sxisons include:

• Produces a poster.This not only gives students the opportunity to demonstrate their knowledge and understanding, but also enables them to use drawings and graphs to illustrate science concepts.
• Production of an information board on a certain subject that can be used by younger children.
• Write a letter or newspaper article to express a position.

Expansion of a solid: Bol and Ring

When both the ball and the ring are at room temperature, the ball can fall through the ring.Ring again.

Keyword:Lower material, heating, cooling, expansion, expansion, contraction, contracts particles, vibrations, vibrates, energy

Expand a liquid: Modelthermometer

Fill a boiling tube with colored water and then place a narrow glass tube (inserted by a cork or bung) in the neck of boiling tubes: make sure the end of the glass tube is in the water.Cooking tube, if you have to see the column with colored liquid in the glass tube, it becomes higher and higher because the liquid is expanded when heated.

Keyword:liquid, warmth -expansion, turning off, particles, exercise, energy

Expand a gas: liquid in a tube/bubbling flasks

You can show this by using a test tube or cooking tube with a piece of capillary tube that is inserted by a bung.Get up in the pipe: it is pushed up by the air in the test tube.

Another way to do this is to use a cooking tube or bottom tube with a narrow glass tube that is inserted in it.Heat the air in the flask with your hands, air bubbles from the hose in the water.

You can demonstrate the opposite process - the contraction of a gas if it is cooled - if you have an empty plastic drinking bottle with a screw cap.Pour a little hot water into the bottle, destroy it and then pour it out again.Screw the top again.

Keyword:Gas, heating extension, extension, contracts, contraction, particles, collisions, energy

Resolution and diffusion

Potassium permanganate crystals in water

Buy a glass trough or a large glass cup or glass bowl and place about water in depth.Changes in the water.Allow the water to be completely established and then release one or two (no longer) potassium permanganate crystals in the water.Is the proof that there is some potassium permanganate in that piece of water.If it is left long enough, the purple color spreads over the liquid and the color will be the same intensity instead of being the deepest near the crystal.Is proof of diffusion.

Keyword:Potassium permanganate crystals, sturdy, dissolved, dissolved, diffusion, particles, collisions, random

Perfume in the air

Spray some strong perfume in a corner of the room.Cover your students to set up their hand when they can smell perfume.Potassium permanganate -experiment shows that diffusion is faster in gases than in liquids.

Keyword:diffusion, particles, collisions, spaces, random

Introduction

Organizing practical work is an important part of a science teacher.Practical work requires careful planning and some improvisation.

In this unit we take the subject from the Meet and illustrate three different ways to organize practical work: demonstration, a laboratory parade and to solve a problem.Ahead, while others find the ideas difficult.We have used these activities to show how you can distinguish work and can accommodate students with all the ability.on.Bron 1Offers some ideas about the different ways to distinguish work.

Distinguishes work for students with different skills

As you will of course understand, every student has different skills.Others by listening to and absorbing spoken instructions.Some will easily understand the work, others will take more time.Some will work very quickly through every task that you have set, others will work slowly.It is impossible for you as a teacher to take all the differences that consider all the time, but there are things that you can do to support individuals in a class.

If you have a class of 30 or more students, this may sound like a scary task!There are two important things you have to do to be able to effectively accommodate everyone in your class:

1. Know your students.You have to give them opportunities to work in groups and listen to the conversations;You have to mark their written work;You have to ask questions from individuals in the classroom and you have to encourage them to ask your questions if they don't want to know or just want to know more.If you know who easily understands who finds science difficult, who likes to talk, who likes to write, who likes to draw and who likes to do experiments, you will be in a much better position to help individuals.
2. Know your subject.It is unrealistic to expect everyone to remember everything and understand what you do.

You can take into account the selection of skills within your group in two important ways:

Differentiation of the result

This may mean that you give a number of questions that gradually become more difficult.Everything comes as far as they can.Already with alternative you can set open assignments where students demonstrate what they can do.Present their work, which can be very motivating.

Differentiation by assignment

This includes setting different students or groups of students different assignments.For example, some students in a practical session can have instructions in written form for them, and some can have them in a diagram form, and some can have a combination of both.

You can give a number of questions that cover the basic ideas that you assess that everyone must understand, and a set that is more challenging.

Learning style

There is a lot of research that suggests that different students prefer to learn in different ways.The three learning styles that are more often referred to are visual, sound and Chinaesthetic, that is, preferably students prefer graphs and photos, some learn best by listening and some people prefer to be able to do things.

As a teacher you cannot be expected to always take all students into account, but a good teacher will ensure that their lessons contain activities that all cover the learning styles.

There is a tendency to expect students to listen a lot.Just don't copy

Practical work

Introduction

Practical work is an important part of learning about science and learning to be a scientist.

Tessa Materials are considering practical work in the science of students who discover, learn and verification through observation and experiment with the help of skills and methods used by scientists in the real world.Ensure that their students experience different types of practical work.

Purpose of practical work

Different types of practical work and specific experiments will achieve different goals, but the benefits of practical work include:

• Development of practical skills and techniques such as how to use a microscope.
• Handicely experience with materials and processes that can increase their understanding of science and help retain knowledge.
• Development of study skills such as control of variables, analysis and registration of data and looking for patterns.
• Motivation and pleasure.
• Encouragement and promotion of higher thinking.
• Communication properties.Practical work can offer a context for developing communication skills.

Types of practical work

• Demonstrations- A teacher can decide to make a demonstration of safety reasons or due to lack of time or resources.Experiment or activities before or during the demonstration (for example, predicting whether statements are true or false and then use observations to confirm or change their decision).
• Structured practical -Students carry out an experiment in groups..
• Rotating (circus) handy- Pupils in groups go from one experiment to the next at 'Stations' in the classroom.The experiments must be related and instructions must be short.Particle theory of dust or adjustment.Some stations can contain a short sort or problem to solve instead of an experiment.
• Research- Pupil's plan, feed and analyze their own experiment.It may have the freedom to choose what they are investigating whether the teacher can limit the available material or specify a subject to investigate.Give students usually guidelines on 'the scientific method' or perform an 'honest test'.
• Troubleshoot- This is similar to a study, but students have more freedom of freedom.Good vehicle to promote communication skills.

Organize practical work

Every time you plan an experiment, try it yourself for the lesson.

When dealing with chemicals other than water, students must wear safety glasses.If you are not available, you must use very diluted solutions (0.1 m).0.4 m).

You have to think about how your students get the device they need.

• Give them an activity to do at their desks and even if they do that, you distribute the device they need.
• Spread the different things in the room and ask a person from each group to collect what they need.
• Give the chemicals themselves with a teaspoon on small pieces of paper that they can go back to their place.

Examples of measuring equipment and questions

Here are some general 'fast' questions you can ask students about equipment that they do not recognize:

• • Can you see device names on it?
  • Does it look like something with which you could do electrical measurements?Can you connect electrical equipment?
  • Are there turns that you can run?What happens if you do that?

You can make this easier for students if you make a table with quantities, devices and abbreviations that students can refer to, here is an example:

Examples of stations for activity 2

Remark:If you have a camera (or a mobile phone with a camera), it would be useful to take photos of students when performing some of the activities.Also try to capture some of the variations in how different people interpret an activity (eg station 6 extension or drawing the load in station 7).

Station 1

Equipment and notes

Circuit made with three bulbs connected in series (with a switch in series) for a low voltage -DC supply or battery that approx. 4 V. The voltmeter must be correctly connected over the three lamps using two wires, but the contact toChecking the supply for the circuit must be open to students to close themselves.

Instructions for students

Close the contact and register the Read in Volt.

Station 2

Equipment and notes

Top pan balance or kitchen weights;

Mystery object such as a mass of 20 g or a stone, in a box or bag (so that students do not see what it is and guess the answer).

Instructions for students

Place the bag (box) on the scales and absorb the mass.

Stations 3, 4 in 5

Equipment and notes

Stations 3 and 4 need identical small logs, approx .2 cm thick, but gives a ruler for station 3 and gives a micrometer to station 4;

Station 5 needs a small piece of sponge, approx. 1 cm thick plus a ruler or a micrometer.

Instructions for students

Measure the thickness of the object.

Station 6

Equipment and notes

Measurement of the cylinder or the measurement of jugs with a little water in it.

Expansion 1: Another measuring cylinder and a stone for measuring the quantity of the students.

Expansion 2: a third measuring cylinder and a collection of 10 small stones (pebbles/gravel/shingles, all about the same size and each less than 1 cm over).

Instructions for students

How much water is there in the container?Register the amount of water in the container.

Extension1: Find the Pebble volumes.(Tip - Pebble moves its own water).

Extension 2: You have 10 small stones.

Station 7

Equipment and notes

2 x power meters (spring balance): one of them (a) must hang on a tripod, ready to attach the load, the other (b) must be left on the couch;

A small heavy object to attach to the spring balance.

Keep in mind that students 'go' the load on the hook so that it falls or jumps off.

Make sure that both power meters are correctly reset at the start of the session.zero.Controller so often that nobody corrected it.

Instructions for students

Attach the object to the hook on the instructions of the stream meter.

Now remove the load and connect it to the other power meter so that the load on the couch rests.slowly and steadilyAlong the bank?

Answers and things to discuss with your students

These stations not only offer opportunities to make measurements of a number of quantities, but also to discuss why measurements can vary:

The circuit in station 1 offers the possibility to read a voltmeter.When students don't have to do anything for the circuit, except for closing a switch, some variations in the measurements obtained can probably be made from a corner instead of immediately before that.

Station 2 activity is again a simple measurement with the help of kitchen bowls or an upper pan balance.

Stations 3, 4 and 5 show difficulties because of learning a micrometer.

Station 6 uses a measurement cylinder or is possible to measure the amount of water in the container.The individual stone can lead to more variation, depending on the equipment and methods used.Variation (if you didn't pray them about the use of all 10 stones, you could also ask how many stones they used for the measurement.)

Station 7 uses flow measurements.From results because students want different ideas for how quickly they have to pull it and in which corner they have to draw: some photos would be very useful here.At the same time too.

Examples of questions about all results

• Look at the results for (station X): did everyone in your group agree on the value?If not, why was it then?
• Which stations results showed the most variation?Why do you think it's?
• What amount did you find the most difficult to measure?
• Have stations results show a steady change in value (to get smaller or larger when you went off the column)?If so, why do you think it happened?
• Were the results different if you might have expected them to be the same?
• Which measurements were the most/leasthandle?Explain why.
• Which measurements were the most/leastaccurate?Explain why.

Summary of precision, accuracy and variation for the teacher

Why do measurements vary?

1. Variations caused by the equipment or by the way it is used:
   • The scale is not good enough for the quantity you try to measure.
   • The equipment produces variations in the lecture that are not due to actual changes in the measured quantity.
   • The scale will not be reset if they have been performed
   • The measurements are not performed under controlled conditions (there are, for example, concepts, changing temperatures).
   • Incorrect technology (eg do not read a scale of directly for the needle or indicator or level with the scale marking).
   • Differences in technology/experimental method.
   • The equipment is damaged.
2. Variations in the measured quantity:
   • There is a natural variation in the crowd - there is no absolute, 'true' value, eg length of a leaf, diameter of a seed in the sense that if you chose another leaf or seed, the value would be different, regardless ofHow carefully you have measured it.
   • The value changes over time due to a factor that has not been considered when setting up the experiment (for example, the length of a wire can change if the load is left on it, a previously dehydrated object can show an increase in the volume, because the Harabsorbed can showWater from the area can show another object a decrease in mass due to the losing of water in the area, water fresh from the tap can be at a different temperature than water that is in a room for an hour or more..).

"Exactly" or "exactly?"

Accuracy is about how close a measurement an agreed actual value is for specified conditions.

Precision is about how close a series of measurements matches.

The earth

Diameter = 12,760 km

Radius = 6,380 km

Massa = 5,972 x 10²⁴kg

Crust = 40 km right

Distance from earth to the sun = 1. 426 x 10⁹km

Distance from earth to the moon = 384,000 km

The moon

Diameter = 3,475 km

Jet = 1,738 km

Massa = 7.35 x 10²²kg

Africa

Distance from the northernmost point (Ras Ben Sakka in Tunisia) to the southernmost point (Cape Agulhas in South Africa) = 8,000 km

Distance from the most western point in Africa (Cape Verde) to the easternmost point in Africa (Ras Hafun in Somalia) = 7,360 km

Height of a tree

• Measure the length of the shade and compare it with the length of a shadow that is formed at the same time as a meter rule.
• Measure the length of the shade and also the angle ϑ from the ground at the tip of the shade to the top of the tree (care: don't look at the sun!) Then use
  • opposite = adjacent x tan ϑ
  • Opposite the height and adjacent of the tree are the shade.

Mass of a sheet of paper

Find the mass m of an x ​​sheet of paper and then mass of a leaf = m/x

Area of ​​the palm

Pull around your hand on a piece of square paper and count the squares.

The volume of a stone

Shear methods (see Station 6, Extensions 1 and 2 inResource 4))

Thickness of a piece of paper

Measure the height (h) on a stack with x pieces of paper.A piece = h/x

Mass of rice grain

Measure the pulp (m) of a stack of grain.

You must let more people count the grains and keep checking until everyone agrees.

Press exercised by a student

A student stands on a square paper and someone pulls his feet.

The power they practice (F) is m x 9.8 and is in the Newton.

Pressure = f/a.

Introduction

Science is all around us.Students must learn.Bron 1Give some strategies that you can use to help your students make these connections.This device is not limited to a field - we want to encourage you to develop the habit of relating the science that your students learn in their daily lives.You will use brainstorming as a technique to help them make connections and you will be encouraged to take them out of class.

Students often see science as something they do at school and not necessarily related to their lives.The school that is important can be involved and interested - especially if there is any controversy involved.Keep your students interested in science and help them see how science can help them understand the world.

To make science relevant to daily life

Possible strategies

Class discussion

Where possible, use local examples, but also encourage students to draw on their own experience in the classroom.

Practical work

• Use local examples and materials, such as Hibiscus indicator;
• Give students a challenge with the help of scrap materials, such as pure salt.

Research project

Students can find information from local newspapers or magazines or interviews adults in society, such as breweries, mechanics or health workers.

Use the school grounds

In addition to the obvious opportunities for organic studies, the grounds of the school are a source of educational examples in other topics such as corrosion, structures and forces.

Day visit

Visit local industries, agricultural places or museums.The effective teacher will link this to the classroom both before and after the trip.

Homework

Ask the students to write about examples of science around them (eg chemical change in the kitchen or effort on the football field) or to bring materials to the classroom.

Write tasks

Use local problems as an incentive for creative written work, such as a letter to a newspaper or radiocript about local environmental or health problems.

Tasks

• Interviews - A child can be 'expert' and the interviewer can ask questions as if he is producing a news company for the radio.
• The students make a decision on a local subject, such as health promotion or energy supply.

You have to make a file yourself and keep all newspaper and magazine items that you find that contain or about scientific problems.Every time you start a new topic, you wonder how it relates to daily life and help your students make these connections.

Brainstorm

Brainstorming as a class or in smaller groups can help students make connections between the science they learn in class and their daily lives.

Brainstorm

Brainstorming is a group activity that generates as many ideas as possible about a specific problem or problem, then determines which ideas offer the best solution.Helps students:

• Understand a new topic
• generating different ways to solve a problem
• Be enthusiastic about a new concept or an idea
• Feel involved in a group activity that reaches agreement.

Brainstorming is especially useful to help students make connections between ideas.In science, for example, it can help to appreciate the links between the ideas they learn in the classroom and scientific theories.

As a teacher, a brainstorm at the start of a subject gives you a good idea of ​​the scope and depth of knowledge that has already been recorded by the class.Collective ideas that you can refer back to as the subject of progress.

How to make a brainstorm

Before you start a session, you must identify a clear problem or problem.Probably answers.And power.

There must be a large sheet of paper that everyone can see in a group of between six and eight students..

Before the session starts, the following rules are made clear:

1. Everyone in the group must be involved.
2. Nobody rejects the ideas or suggestions of other people.
3. Unusual and innovative ideas are welcome.
4. Many different ideas are needed.
5. Everyone has to work quickly;Brainstorming is a fast and furious activity.

Session

The role of the teacher is originally to encourage discussion, involvement and recognition of ideas..

• summarize what they did well for the class
• Ask them what they found useful about their activity.

Daily examples of print

This is followed by some real examples of pressure in action:

• If you wear a heavy bag, narrow handles or belts are cut into your hands and shoulders, but wide handles and belts are more comfortable.
• Surely heels on shoes sink further than wide, flat heels.
• To spread your weight over a larger area, you tell you to sink.
• Heavy vehicles used on softer soil must have larger, wider tires.
• A sharp knife has a narrower leaf edge than a stump and is easier to cut.
• Nails and couplings have a flat hammer head plus a sharp point to make it easier to hammer in wood, but also a leak of tires.
• Large machines to dig, grab or liftuseHydraulic print systems.

Below are some daily items that depend on pressure at work:

• Sudepuder
• Sucks a drink with a straw
• sifoner
• Spray
• Bicycle pumps
• Water pumps
• Hydraulic jacket for lifting cars
• Pneumatic controls
• Vacuum cleaners.

Examples of physics in action

Places to visit and examples that you might see

Some examples of strengths

Hydraulic Jack:

You use a small force, but drain to increase the large load at a smaller distance.

Input pressure = output pressure because the pressure is transmitted by oil.

• Small input stamp cylinder with A1 area, small input power F1
• wider output stamp cylinder with area A₂, larger exit -power f₂
• Power on Output Stamped

Handles, eg SEAW:

Clockwise turning strength x distance from pivot = against the clock in turning strength x distance from pivot

Cut tools for example secateurs, shears:

Background information about insulation and keeping the water cool

• Energy (heat) Transfer from hot objects to colder items.
• Everything that is warmer than the environment becomes cooler by transferring energy to the environment (so that they get warmer);Everything that is cooler than the environment gets warmer (and the environment becomes cooler) when energy is transferred from the environment to the object.
• If you leave something long enough, it will reach the same temperature as the environment.
• To keep a warm object warm or to keep a cold object cold, delay or stop the transfer of energy (heat).
• Energy (heat) is transmitted by wire, convection and radiation.
• Metals are good conductors, but plastic or materials with many air holes such as foam or bubble wrap are bad conductors (nor good insulators).
• Using thermal insulationofinsulatingA hot or cold object means that the object is packed in a material that is a poor thermal conductor.
• The thicker insulation, the better it works.
• Heat (energy) is transmitted by a liquid such as air or water using convection flows.Air or liquid is cooled, it is close again and sinks.
• Building design can use convection flows to keep the building cool: to make this, the hot air can rise through the building and flee the top and draw cool air at the bottom.
• Glossy or white surfaces reflect the most radiation, while black surfaces are the best absorbes and transmitters.Spray them with shiny paint) or white surfaces to reduce absorption.
• Vacuum cabbage reduces the heat transfer by all three mechanisms: the silver -colored layer reduces the transmission with radiation, the vacuum means that there is no air that makes loss of convection possible and the insulating foam under the cabinet reduces losses by wire.
• Thick coatings also help keep cool things cool, because more energy is needed to warm up the cover material.
• Water has a highSpecific heat capacity, which means that it needs a lot of energy to increase the temperature so that it stays the temperature longer: rivers and lakes are slower to warm up than the surrounding country;Cool longer than leaving them on the table alone.
• When a solid melts, it absorbs energy from the environment, but it stays at the same temperature until all solid has become in liquid.A relatively large amount of energy to melt, used for cooling coats to transfer food or medical supplies without cooling (when used, or in plaster to keep rooms cool, they are mentioned 'The usefulness materials'Of kortweg PCM's.)
• When a liquid evaporator, it uses energy from the environment to do this, so that we can use evaporation to keep things cool: let the water evaporate from your skin instead of using a towel to wipe yourself, you feel youCooler and wrapping a bottle A damp towel helps to keep it cool for a long time.

How can we keep the water cool for as long as possible?

A cold drink directly from a fridge or cooler can be very refreshing, but it doesn't stay cold for long!

Work together with your partner to design a way to keep the water cold in a hot climate.You must create and test your design and then present a report explaining how it works.

The writing frame below can help you.View your report by answering the questions:

Introduction and plan

Results and evaluation

Introduction

When your students look for a job, the qualifications they have will clearly be very important.Potential employers will also be looking for people who are creative and who can solve problems;For yourself.Case studies and activities in this device are designed to show you how you can give your students the opportunity to be creative and develop their 'thinking skills'.Bron 1.You have to think about how you can create an atmosphere of excitement and research in your class.If you can do this, students will ask questions and easily contribute their ideas.Really enthusiasm about the topics that you teach.

Creativity is about the possibility of thinking, not only remembering, but to use, to propose, expand and make analogy.Students who are particularly talented in the topics of humanity and who like to write, perhaps like to write about science in the form of a newspaper article or a poem.Choice.

Problem solution and creativity

By being resourceful and fascinating variation, you can motivate your students.Can look!

Creativity

Creativity is about the ability to think.Ideas.They must also feel safe at the reception they get before they make such suggestions.

Of course some teachers will be very creative, but some will not do that - and that is fine as long as you are resourceful and willing to try new ideas.In different contexts you can use news from radio, TV or newspapers and relate this to the science that you teach.For everything you will create an atmosphere of excitement and study with dramatic demonstrations, enthusiasm or amazing and incredible facts.

Troubleshoot

Helping students in developing problem -solving skills is a often quoted goal for science teachers.Explain how you worked it up and why you found it hard.It can solve problems with the development of thinking skills.

• Encouragement of questions generated by students.The action of asking questions requires involvement and creative thinking, two cognitive core strategies.
• Be aware of 'goal'.Students must be encouraged to ask: what is it about? "" What does this concern? "" Why do you want us to do this? "
• Set open activities.Teachers must set up activities that can be treated in various ways, so that children have to think about how they will tackle the problem.
• Planning.Teachers must give children opportunities to plan their problem -solving strategy in a systematic way.
• Paraphrase.It is known that you really get to know and understand ideas while you try to teach them to someone else.
• To learn to learn (metacognition).Teachers can encourage children to become more aware of their learning by making them think about why they did not understand and what strategies have helped those who can be useful in the future.

Reference

Wellington, J. Og Ireson, G. (2008)Science Learning, Science Teaching.Abingdon: Routledge.

Promotion of cross connections and skills

power

This source is for use with activity 2.

Forces can change the shape of an object can lead to it moving faster or slower or changing the direction in which it moves.

If an object does not move or moves in a straight line in a straight line, the forces must be balanced on it.

The greater the power of an object, the greater the gear (change in speed) it produces.

Forces (and speed and acceleration) are vector quantities - they have size and direction.represents the power.

Use Power -Diagrams with students

Asking students to draw graphs about the forces that work on an object or power to add an incomplete diagram - is a great way to investigate what they think is happening and to encourage the discussion.

Giving photos for labeling instead of asking students to draw the objects can help prevent the problem from students who give their drawing ability or constantly spend a beautiful drawing instead of thinking about science.Identify the forces that work on an object and to show in which direction they act.

For older students you can introduce some additional guidelines:

• Streams are straight arrows (not bent).
• The arrow must start with the part on which it works and points in the direction of the power works.
• The longer the arrow, the greater the power.
• If two forces are in balance (then the object does not move steadily), the arrows will have the same size and start from the same point, but go in opposite directions.
• If two forces on an object are not in balance (so the object accelerates), the greater power will be in the direction that it speeds up and the arrow of this power will be greater.

Identification of the forces that work on objects: some examples

The forcemeter in diagram 1 shows that a small force is based on when the mass is in water.

The mass that hangs on the forcemeter, the spring pulls down less in water.

The mass is unchanged:Pull the gravityOn (red arrow, on both graphs) the same is in air and in water, so the weight is unchanged.strictForce (blue arrows, only on the right photo) on the mass.

The balloon in diagram 2 has only a small mass, soPull the gravityIs quite small.push downTo get the balloon under water.You push it under the balloon, the harder you have to push to keep it there.

As you push the balloon down, you see the water level rising: the water that pushes you out of the road (displacement) while the balloon goes under water.

The amountstrictDepends on the amount of water compensation through the balloon.

Diagram 2Push a balloon under water

Diagram 3A needle that flows into water

A needle does not weigh much, but it does not move much water because it seems to be on the surface;So what does it hold?

Add a drop of detergent to the water.

Identification of forces during a bungee -spring

There are three phases that must be taken into account:

1. On the way down
2. At the lowest point of the jump
3. On the way back

1. On the way down there is no excitement in the Bungee Rope.
2. At the lowest point in the jump, the voltage in the bungee crack is maximum and is sufficient to prevent them from falling longer.
3. The elastic rope raises the sweater again: the rope is no longer stretched, so the upward characteristic of the voltage is smaller.

To let students generate their own questions

For students to ask questions about something they study, they must feel that asking questions is a good thing and that they will not be laughed at or found stupid to ask.

Things you can do

You can encourage students to ask questions by giving answers such as' it's a good question!vanThinking? "Or" Should we find out? "Or" Hmmm ... Let's find out! ".

This increases two important points:

1. It's usually betterdoesn'tTo just give students the answer, but to encourage more thinking.
2. You must have thought about the kind of question that students can ask so that you have things ready in your room to try ideas.predictions whether it can mean that the internet or reference work is to see if they have answers.Help them reformulate these suggestions for something useful, instead of telling them what they should look for.

Another way to promote a spirit of studies is to have something made and worked, or some unusual objects such as 'Stamps' so that students can ask you 'What is it?'

When something unexpected happens, it can bring people through their understanding, so it is important to record demonstrations that contain something that surprises students with demonstrations that illustrate an important point.happen before they see whatDoinghappen and to be willing to repeat an activity so that they can get the full advantage of this.

You can show that your query appreciates by being a role model.If something 'strange' or unexpected happens, let them ask you why it was and be ready to look for answers.

Solving problems - Think about thinking

Here is a challenge!

A lump of plasticine sinks when you release it in a bowl with water, even if you carefully lower it.

Try your idea and then compare your solution with that of others.

Expanding the work of currents and sinking to offer an opportunity for differentiation in a real problem -solving problem solution

This source offers an expansion of activity 3.

The context and the problem

Recycling is important to save valuable sources when the item can no longer be reused.Products have a recycling code about those who tell you what they were made of, but you cannot always see this code on a piece of dirt plastic.)

Background information

A method that recycling companies use to sort mixed plastic waste isFlotation: Different polymers have different densities, so although a current in a certain liquid (because the polymer is less dense than the liquid) will sink others (because the polymer is closer than the liquid).Solution and glycerol (propane -1,2,3 -trio) -can sort the most polymers.

The ordinary polymers and liquids (boldly printed are displayed here in order of increasing density:

Pp (polypropylene), PE (polyethylene),water, ABS (Acrylnitril butcodes styrene), polystyrene,Saturated saline, PMMA (polymethyl methacrylate, also known as acrylic or perspex), PC (polycarbonate - density varies),,glycerol, PC (polycarbonate - Densitet Varier), PET (polyethylentereefhthalate), PVC (polyvinyl chloride).

How the process works

All the plastic waste is cut into small pieces before the batch is added to the first tank (water, the least dense of the three liquids) (this is important because lid and bottle with many plastic bottles will be of different materials and because if you are youUses a whole bottle, it has air in it, so that you do not look at the density of the plastic but at the bottle.) All bits that are beaten away and all the pieces that sink in the next tank, and the process is repeated.(Note that, depending on what was in the original mixture, you may have a type of polymer or that you have two or even three polymers in each of the last, individual groups and you may have to use other tests to find out which oneBits were a certain polymer: you cannot see polyethylene and polypropylene from this method because they both flow into water.)

Set a differentiated task

You can do the amount of challenge of:

• The way you words about the task words
• the materials that you deliver and how you deliver them
• the amount of information or guidance that you provide.

Some different ways to set the task

You must offer cups or bowls for testing samples with every liquid.'Samples' must be small pieces of pure plastic.Get rid of waste and therefore students can dry dry before they are placed in the next liquid.

• Give some identified tests and some 'mysterious' tests and ask students to identify 'mysteries' tests.
• Give some identified samples and ask students to investigate which flows and which sinks into each liquid, and then take an identification test.Jo more polymers, the harder the task is.
• Give unknown samples and the information about relative densities and ask students to suggest what each test is.XofyIs easier than identifying without hint options.
• Give unknown samples and the information about relative densities and ask students to suggest what every sample isand evaluate the method.This adds a different question because students have to think about which strengths and weaknesses are.

Some things you could use as sources of different types of polymer

PP Polypropylene: Bottles of tops, some cosmetic bottles, yogurt pots, some food bins

PE -Polyethylene: Bleek or detergent lessons, bottles for silent drinks, some cosmetic bottles

Pet Polyethylene Terephthalate: Shampoo -Bottles, Fizzy Drinks -Bersessen

PVC Polyvinylchloride: plastic tubes and cable aids

PS Polystyrene: Plastic Bestics, 'Foam' Mad Cardone, Drink Cups

PMMA -polymethylmethacrylate (Acrylic, Perspex): plastic heersers, Clear Drinks Cups.

Introduction

Being an effective science teacher means that it can be very clear to explain difficult ideas.About the science that is 'wrong', especially about the more abstract topics.To be identified and handled before the progress can be made.It is often not enough to explain the ideas;

In this unit, the three activities build on each other and enable you to gradually develop their understanding..

Misunderstandings about magnets and magnetism

Researchers have discovered that there are certain misunderstandings about electricity and magnetism that are very common.

Misunderstanding: All metals are attracted by a magnet

Not all metals are attracted by a magnet.'Copper coins', who are attracted to a magnet, are not actually a copper, but a buyer -nickel alloy.

Misunderstanding: if something is attracted by a magnet, it is a magnet

Being pulled until a magnet does not mean that a material is a magnet (but it is a magnetic material and can be made to a magnet).This time rejected by the magnet, the object is also a magnet.

Misunderstanding: The Magnetic Arctic, ie the Pole of the earth in the northern hemisphere is magnetically a North Pole

Northern sizes of magnets are the posts that point to the north.If posts, unlike posts, so the magnetic North Pole of the earth is actually a magnetic South Pole because it attracts the North Pole in a magnet!

Misunderstandings about a job for a pioneer and electricity

Misunderstanding: You only need a wire to make a circuit with a battery and a pear

If students have seen an electric light hang on a ceiling on the ceiling or electrical equipment with a lead to a plug, but have never built a circuit with batteries and pears, they can believe this (they can also believe that if you use two threads, the cord of one end of the battery is the one who counts and the other is simply to light as a 'return route'.), Not the glass) for the lamp.

Misunderstanding: power is 'used up' while it flows around the circuit

Power is not used up: the power is the same all the way around a series circuit.Be the same brightness.

Misunderstanding: The power starts from one end of a battery and in turn flows through each part of a circuit until it comes back to the other end of a battery (eg Kstil battery)

The current immediately flows into all parts of a circuit when there is a complete circuit.Even if you had a huge circuit that went around the classroom, all pears would light up at the same time, not after the other.

Magnets, Magnetic Materials and Non-Magnetic Materials

Proposed circuits and descriptions

This source is for use with activity 2. You can add more of your own that applies to your syllabus.

A circuit with a cell (battery) and a pear.
A circuit with a cell (battery) and two balls in series connected.
A circuit with a cell (battery) and two lamps connected in parallel.
A circuit with two cells (batteries) and two bulbs in series.
A circuit with one cell and a resistance in which one ball in series is connected to the resistance and the other lamp is connected to them in parallel.
A circuit with a cell and two bulbs parallel to a switch that controls both lamps.Of A circuit with a cell and two bulbs parallel to a switch between the bulbs and the battery.
A circuit with a cell and two bulbs in parallel, with a switch that controls only one of the bulbs.Of A circuit with a cell and two bulbs parallel to a switch on one of the branches.

Teacher instructions for Rol -Games Games

Here are two role plays that you can use to model what is happening in an electric circuit with a small group (before use with activity 3).

Remark:The descriptions explain the various parts of roll games ('this person is the battery', 'this is charged to move the circuit' etc.).All this, but just say that this is a role to play to model what is happening in an electric job.what must we do, ask them questions like "Who is the battery?" "What represents the moving costs?" "What represents the resistance?" Or "How does it show that energy is being transferred?"

Such a copper

What you need:A packed sweets, two boxes and some paper cups.

What must we do:

• Start with everyone except one in a circle.This outside the circle is an observer.
• A person (the battery) has a box with some packed candy in it: they pass on a candy every second to the person on the right side who immediately transfers each candy to the person to the right, and so on (it can help someone outside the circle to do thisTime to hold time by tapping the table once every second.)
• A person in the circle has a cup.Located behind the person to the left of the 'battery' and folds a cute back to the battery every time the person they are behind.In the rhythm before you make changes.
• Now give a cup to another person, so there are now two lamps/resistors in the circuit.
• Now give another in the group a box and half of candy.Speed ​​passes that candy around the circle and the observer claps twice as fast.

This model is good because you can see that the number of moving loads remains the same.The risk that students will think that the addition of batteries will add more costs, even if you have not received more sweets than before: focusing attention on the speed with which candy passes the observer., but ask them to pass on round candy with twice as much as flap with the double of the speed they did earlier.)

In the ideal case, the candy would be slightly smaller every time they passed the 'lamp' that represented the transfer of energy to the lamp.Candy would be used until the last time - which is the battery without energy.Electric circuits that are not properly displayed in this model: transfer energy from the circuit to the lamp.The other model is better in this respect, because students can feel the energy when the heat is generated by friction.

Reb

What you need:A (large) loop of ropes, ideally with a pattern or markings on every meter, so that you can see how fast it goes.

What must we do:

• Everyone in the group is in a circle, so the rope loop is not pulled too tightly but is nowhere.
• A person is the battery: they pull the rope aroundStable, ie a steady amount of properties.
• All others are the resistance: they take the rope very easily while it goes around to slow it down.Rope When it goes around, the more energy is transferred to their hands (care for painful hands and friction burns caused by people who pull the rope).Do not start to pull against the resistance.)

This model is good becauseIt shows that as the current flows around the circuit, the loads move around the circuit at the same time.HoweverIf the 'battery' starts to pull harder to move the rope, students can think that the addition of more resistance will make the battery more difficult to keep the power the same.

Ask the class for each model:

• What is the circuit in this model?
• What represents the load that moves around the circuit?
• What represents energy in the circuit?
• Where does the current energy collect?
• Where does that energy give up?
• In what ways does this model seem like your own ideas about electricity?
• Which model is better?