ENERGY-RELATED ACTIVITIES

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1 ENERGY-RELATED ACTIVITIES 1. WIND POWER - MAKING A WINDMILL Aim: In this activity you will make a windmill and test its operation in still and windy conditions. Materials: Scissors A piece of cardboard or thick paper, approx 15cm square One pin or a double-pronged tack (split pin) A wooden ruler or straw Safety: Care needs to be taken when using scissors, pins or tacks. For younger students, teacher should assemble the windmill. Method: 1. Draw diagonal lines from one corner to the opposite corner on the cardboard sheet. 2. Mark pin holes in each corner and in the centre of the square card as shown. 3. Cut half way along each line from the corners. 4. Fold each corner over towards the centre. 5. Pin the card through each corner and the centre onto the end of a ruler or straw. 6. Make sure your windmill can spin easily/freely. 7. Now take the windmill outside and position it so that the blades circulate at the greatest speed. (If there is no wind, then go to step 8.) 8. Note the orientation of the blades for maximum speed. 9. Take the windmill inside and compare its speed now. Blow against the blades to create a light breeze. Windmill

2 Interpretation: 1. Write a few sentences describing what you have found. 2. How could you improve the design of your windmill? If there is time, test these suggestions Investigate how wind turbines produce electricity at the following link: 4. Trace some of the energy changes from the movement of the wind to the production of electricity.

3 2. SOLAR POWER - MAKING A SOLAR HOT WATER SYSTEM Aim: In this activity you will build your own solar hot water system. Materials: Thermometer Large plastic jug Water Two small black garbage bags Two shirt boxes with clear plastic tops A sunny location Safety: Care needs to be taken when recording the temperature of the water. Water left in the sun for long periods of time can get very hot. Method: 1. Place 1 litre of water into a plastic jug. 2. Pour 500mL of water into each black garbage bag, record the starting temperature of each, and put a knot in each end to keep them closed. 3. Place each of the black garbage bags into a shirt box. 4. Put the clear plastic lid over the top of the shirt boxes. 5. Place one in direct sunlight and leave one on the bench in the classroom for at least one hour. (Leaving them for 2-3 hours would be better.) 6. Record the temperature at one hour intervals for three hours. (Untie the knot and place the bulb of the thermometer in the water or make a small cut in the black garbage bag and push the bulb of the thermometer through this. Take care not to spill any of the water.) Solar hot water heater Results: Time (hours) Temperature of Water in bag in the Sun( C) Temperature of Water in bag in the Classroom ( C)

4 Interpretation: 1. What was the total increase in temperature for the water in the bag in the sun?. 2. What was the total increase in temperature for the water in the bag in the classroom?. 3. Was the increase at a constant rate? i.e. did the temperature increase by the same amount each hour? Why was a black bag used? 5. What factors were kept the same between the set-up in the sun and the one left in the classroom? i.e. the variables that were kept constant or controlled. 6. What factors or variables were different between the two set-ups? 7. Why did we bother to have a set-up left in the classroom and record any changes in its temperature? 8. Are there any aspects of this experiment that don t meet the requirements of a fair test? 9. How effective do you think the solar hot water system was at heating the water in the black bag? 10. Are there any other applications of using solar energy that you can find? Investigate further ways of using solar energy and the benefits and disadvantages of its use at the following link:

5 3. HYDRO-ELECTRIC POWER - MAKING A WATER WHEEL Aim: To make a water wheel and investigate hydro-electric power. Materials: Plastic soft-drink bottle Styrofoam disc Scissors Knife Knitting needle Water Jug Hole puncher Safety: It is best if the teacher performs any steps involving the use of scissors or knives. Method: 1. Use the scissors to remove the top half of a plastic soft drink bottle. 2. Cut two U-shaped sections out of opposite sides of a drink bottle as shown in the diagram below. 3. Using a hole puncher or the pointed end of the scissors, make two holes in the opposite sides of the plastic bottle as shown. 4. Make a hole through the centre of the Styrofoam disc using the pointed end of a knitting needle. 5. Use the plastic left over from the U-shaped sections to make small plastic blades as shown. 6. Using the knife, make incisions in the Styrofoam disc so the plastic blades fit in snugly. 7. Push the knitting needle through one hole in the side of the drink bottle, then through the centre of the Styrofoam disc and out the other hole in the opposite side of the plastic bottle. 8. Pour water from the jug so that it falls on the plastic blades. This should make the Styrofoam wheel turn. This creates a moving water wheel. Interpretation: 1. As water is held in the jug above the water wheel, what type of energy does it have? 2. When the water hits against the blades and causes the wheel to rotate, what type of energy does the wheel now have? 3. The knitting needle now rotates too. What type of energy does it have?. 4. The falling water pushes against turbine blades causing them to spin. As the turbine spins in a hydroelectric power station, it turns a generator that produces electricity. Find out some of the advantages and disadvantages of using hydro-electric power and other applications of hydro-electric power at: 5. In your model above, list some variables that affect how fast the water wheel spins. Design an investigation to test one of these factors. How will you make it a fair test?

6 4. ENERGY EFFICIENT TORCH Aim: To use a torch that is powered by movement. Materials: an energy efficient torch (You can purchase these in many department stores or borrow one through Queensland Museum Loans) Method: Shake the torch for several minutes. This causes a magnet to move up and down in a cylinder around which there are coils of wire. What type of energy does the magnet have as it moves backwards and forwards?. When there is movement in a magnetic field it causes electrons in the wire to move and this creates an electric current. This is also called electro-magnetic induction. When the torch is switched on, the bulb will now light up. Let s Investigate In this investigation you will think about experimental design, fair testing, setting up data tables and graphs, interpreting data, and suggesting improvements in experimental design. In your groups, discuss the following questions and write up your answers and experimental plan in your science journal. 1. Design an experiment to investigate the relationship between the time the torch is shaken, and the time the bulb glows. If you double the time you shake the torch, what effect do you think this would have on how long the bulb will glow? Write a prediction or hypothesis in the following format: If.then 2. How will you ensure that it is a fair test? 3. What data will you collect? 4. How will you record your data? Set up some data tables and graphs to display any relationships. 5. Perform the investigation, analyse the data and write a conclusion. Was the original prediction supported by the results? If not, why not?

7 5. GREENER AND CLEANER SURVEY The following are some ways of saving energy. Take the survey home and tick the boxes for practices that your household already does. Add up all the ticks and see how you rate. Consider areas where you and your family need to improve in your energy usage. Tips for the Kitchen Use a microwave or electric frypan instead of an oven Run the dishwasher only when it s full Put lids on saucepans when cooking Use the right-sized saucepans on the right element or burner Defrost fridges and freezers regularly so they run efficiently [Did you know small appliances such as microwaves, electric kettles, vertical grills and electric frying pans are more energy efficient than an oven or stove?] Tips for Lighting Turn off lights when you leave the room Replace incandescent globes with compact fluorescent lights Keep light fittings, reflectors and lamp shades clean Use dimmers to reduce electricity consumption where they are fitted to a light Use natural light whenever possible [Did you know that energy efficient bulbs use 80% less energy than incandescent bulbs and last up to 10 times longer?] Tips for Heating and Cooling Turn down your heater thermostat one or two degrees Turn up your air conditioner one or two degrees to 25 C or more Service you heater or air conditioner regularly Turn off heaters and air conditioners in room that aren t being used Use heavy curtains to minimise heat loss Install insulation in the ceiling [Did you know that every extra higher degree of heating or lower degree of cooling can increase running costs by around 10 to 15 percent; that fully insulating your house can reduce heating and cooling costs by 50 percent; and that solar, gas or electric heat pump systems are more energy efficient that an electric hot water system? Try to set your heating to C and cooling to C] Tips for Travelling Use public transport, walk or cycle Avoid peak hour traffic Check tyre pressure Car pool to work or school [Did you know that under-inflated tyres increase fuel consumption; that you can use up to 30% less fuel by driving at a speed of 80km/hr rather than 110km/hr; and that walking to school or work will use less energy and increase your fitness level?]

8 Tips for Water Usage Take short, four-minute showers Have AAA showerheads installed Get a professional to reset the thermostat on your hot water system to 60 C Turn taps off completely to prevent drips Insulate exposed hot water pipes [Did you know that by taking shorter showers you can save 12 litres of water and 0.5 kilogram of greenhouse gases per minute; and that 27% of the energy used in an average Australian household is used just to heat water?] Tips for Laundry Usage Wash clothes in cold water Adjust the water level for each load or only wash full loads Use the suds save option on the machine Dry the washing on a clothesline rather than using the dryer Iron a whole load of clothes rather than one at a time [Did you know that ironing clothes in loads saves energy wastage in reheating the iron; that front loaders are usually more energy and water efficient that top-loading machines; and that each wash load uses 65 to 120 litres of water?] Tips for General Usage Turn off electrical appliances at the wall when not in use [Did you know that in the average Australian household, appliances on standby can account for up to 10 per cent of the electricity bill and that this can generate over 750 kilograms of greenhouse emission each year?] HOW DID YOU GO? Add up the ticks above and compare your total with the statements below: Well done. Your household is using high-level savings and is energy efficient Your household is very energy conscious but you can save more Your household is well on the way to significant savings but there is a lot more that can be done Your household has made a good start. There are plenty of ways to save energy and money. 0 5 Your household needs to reduce its energy consumption by practising many of the tips suggested. You may like to investigate your carbon footprint at the following link: