Red Line 4, Coursebook

one hundred and seven 107 Step 3: Energy changes Energy changes happen all around us, every day. Example: Driving a car chemical energy (in the fuel) kinetic energy (the car moves) thermal energy (the engine gets hot) Use the example as a model. Show the energy changes that happen … 1. … in a light bulb, when the light is switched on. 2. … in a campfire. Step 4: An experiment with thermal energy Thermal energy is ‘lost’ every day, for example when warm water cools down. (But remember: energy that is ‘lost’ like this does not disappear. It just spreads out so thinly that it becomes very difficult to do anything with the energy.) a) How can you keep a liter of warm water warmer longer? Try out the three methods in the picture. Measure the temperature of the water at the beginning and the end of the experiment. Which method was best? b) Write a report about the experiment. Use the tips below. 1. Hypothesis . What did you think would happen before you did the experiment? (We wanted to show that … . We expected … because … .) 2. Give a list of the equipment you used. 3. Describe your method . (First we … . Then we … .) 4. Give your results . You can show the results in a table / in a list /… . 5.  Write your conclusion . What do the results tell you? (We were right. The results show that … . We were not right. We expected that … but … .) WRI T ING SKI LLS c) Think about how you could use the results of this experiment to save energy at home and at school. engine !*endZIn? – Motor , to cool down !ku:l *daUn? – abkühlen, to spread out !spred-*aUt? – sich verteilen, liter !*li:tE? – Liter, method !*meTEd? – Methode, to measure !*meSE? – messen, temperature !*temprEtSE? – Temperatur, thermos flask !*T3:mOs +flA:sk? – Thermoskanne, hypothesis !haI*pOTEsIs? – Hypothese, Annahme, conclusion !kEn*klu:ZEn? – Schlussfolgerung S ä chemical energy thermal energy light electrical energy bottle in a bag bottle thermos flask A project E Nur zu Prüfzwecken – Eigentum des Verlags öbv