You could use an elevator or the stairs to lift a box to tenth floor. which has greater power?

Stairs don't have any power at all. All the energy used to climb them

has to come from your muscles.

An elevator gets its power from the electric motors that lift it. All YOU

have to do is stand there and look around.

All of this is a big part of the reason why elevators have become so

popular, and why no buildings with more than a few floors were built

before elevators were invented.