Which energy changes take place when a pedalling cyclist uses a generator (dynamo) to light his bicycle lamp?
A chemical → kinetic
→ electrical → light
B electrical → chemical
→ kinetic → light
C kinetic → chemical
→ light → electrical
D light → electrical → kinetic → chemical
Correct Answer: A
Explanation: We know from
the law of conservation of energy: Energy cannot be produced or destroyed
rather we can just transform energy from one form to another. Here, chemical
energy of the cyclist’s body produces kinetic energy through pedaling the cycle.
This kinetic energy is then transformed into electrical energy by the dynamo of
the cycle and then in the lamp electrical energy is changed into light energy.
Hence the correct answer is A.
