Answer:
180 W
Explanation:
The work done by the man against gravity is equal to its gain in gravitational potential energy:
where
(mg) = 720 N is the weight of the man
is the change in height
Substituting,
The power he must deliver is given by
where
W = 3600 J
t = 20 s is the time taken
Substituting,
Answer:
Energy conversion in flashlight.
Explanation:
When the switch of a flashlight is on, then the batteries inside them will be connected in a circuit and chemical energy from the batteries will be converted into electrical energy and then the electrical energy will be converted into light energy.
Light energy is also called electromagnetic energy.
Hence, among the given options the correct one is the first option that is:
1. Electrical energy into electromagnetic energy is the answer.
