2. (a) A train is powered by a diesel engine - Edexcel - GCSE Physics - Question 2 - 2013 - Paper 1
Question 2
2. (a) A train is powered by a diesel engine.
The diesel engine is used to turn a generator.
The generator provides electricity for electric motors which drive the w... show full transcript
Worked Solution & Example Answer:2. (a) A train is powered by a diesel engine - Edexcel - GCSE Physics - Question 2 - 2013 - Paper 1
Step 1
Draw one straight line from each train part to its useful energy transfer.
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Answer
Here are the connections:
Diesel engine → Chemical to electrical
Generator → Electrical to kinetic
Motor → Kinetic to chemical
Step 2
Calculate the amount of energy wasted in one second in the generator.
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Answer
To find the energy wasted, we subtract the useful energy from the total energy supplied:
Energy wasted = Energy supplied - Useful energy
Energywasted=1400extkJ−1300extkJ=100extkJ
Step 3
Calculate the efficiency of the generator.
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Answer
The efficiency can be calculated using the formula:
ext{Efficiency} = rac{ ext{Useful Energy}}{ ext{Total Energy Supplied}} imes 100
