Energy
(a) The photographs show two ways of supplying thermal energy - Edexcel - GCSE Physics - Question 1 - 2015 - Paper 1
Question 1
Energy
(a) The photographs show two ways of supplying thermal energy.
Use words from the box to complete the sentence under each photograph.
(i) The photograph sho... show full transcript
Worked Solution & Example Answer:Energy
(a) The photographs show two ways of supplying thermal energy - Edexcel - GCSE Physics - Question 1 - 2015 - Paper 1
Step 1
The kettle transfers __________ energy to thermal energy.
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Answer
The kettle transfers electrical energy to thermal energy.
Step 2
The barbecue transfers __________ energy to thermal energy.
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Answer
The barbecue transfers chemical energy to thermal energy.
Step 3
Calculate how much of the 200 J of energy is wasted.
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Answer
To calculate the wasted energy:
Wasted Energy = Total Energy - Useful Energy
Wasted Energy = 200 J - 180 J = 20 J
Thus, wasted energy = 20 J.
Step 4
State what happens to the wasted energy.
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Answer
The wasted energy is dissipated into the surroundings, typically as heat.
Step 5
Calculate the efficiency of the motor.
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Answer
To calculate the efficiency of the motor, use the formula:
ext{Efficiency} = rac{ ext{Useful Energy Output}}{ ext{Total Energy Input}} imes 100
