Question

Two people who weigh the same amount climb a flight of stairs. The first person climbs the stairs in 30 s, while the second person climbs them in 40 s. Which person does more work? Which uses more power?

Answer 1

Both people does same amount of work.
First person uses more amount of power.

Explanation:

Let the weight of each people be `m`.kg
Both people traverses same distance `x` metres (say).
`:.`Work done (W) by both people `=F*S` Joules.
`:.W=ma*x` Joules [ `a` is acceleration].
`:.` Both people does same amount of work. (answer).

Now, Power (P) = (Work)/(time taken).
`:. P` of first person = `(W J)/(30 s)` `=W/30` Watts.
`:. P` of second person = `(W J)/(40 s)` `=W/40` Watts.
`:.`First person uses more amount of power. (answer).