Question

The energy transfer diagram for a piece of equipment is shown. You are using a hand-cranked flashlight. One minute of cranking typically provides about 30 to 60 minutes of light.

Describe ALL of the energy transformations that are taking place in this process.
Responses
A mechanical energy to heat energymechanical energy to heat energy
B electrical energy to light energyelectrical energy to light energy
C mechanical energy to light energymechanical energy to light energy
D solar energy to mechanical energysolar energy to mechanical energy
E mechanical energy to electrical energy

Answer 1

A, B and E.

Explanation: Your muscles convert chemical (biochemical) energy to mechanical energy when you crank. The crank/generator converts that mechanical energy to electrical energy (E). The electricity powers the lamp producing light (B). Some energy is lost as heat both from friction in the crank and generator (mechanical → heat, A) and from electrical resistance in the lamp. (No solar or direct mechanical→light conversion occurs.)