“Torching Tiny Teddies” Energy Efficiency Experiment
Aim: To test the energy efficiency of a tiny teddy in kilojoules by burning the tiny teddy beneath a test tube of water. The water temperature is then measured to see how efficient the transformation of energy is. It is important to see how efficient the transformation is as it will give an indication to whether burning tiny teddies would be an efficient source of energy.
Hypothesis: It was hypothesised that the temperature would rise due to thermal energy being transformed via radiation. Also that the tiny teddy would not be an efficient source of energy as most of the energy would still be in the bear, and others would be lost through other forms such as heat ,light and sound energy.
- 1 boss clamp
- 1 test tube
- 1 boss head clamp
- 1 retort stand
- 1 heat mat
- 1 tiny teddy
- 1 thermometer
- 7mL of water
- 1 miniature stand
- 1 box of matches
1. All experimenters put on safety goggles, gloves and lab coats.
2. Set up retort stand on the heat mat, and attach the boss head clamp.
3. Fill test tube with 7mL water and place in the clamp
4. Record the mass of the teddy bear and the energy in the teddy bear (per 100g and in KJ)
5. Put teddy on the miniature stand, and adjust the boss head clamp so that the test tube is 1cm away from the tiny teddy
6. Measure the temperature of the water using the thermometer and record the results
7. Light the tiny teddy using matches until the bear is burning
8. Once the tiny teddy stops burning, record the temperature of the water using the thermometer (swirl the water so it evens out).
Using the temperature change we can calculate how much thermal energy was transferred into the water. The change in temperature was a difference of 14’C, from 26’C to 40’C. Therefore to rise 1mL of water by 14’C you need 58.16J.
( 14’C X 4.18J = 58.16J )
To rise 7mL of water by 14’C you need 407.12J, which creates the total energy that’s gone into