A 65kg person climbs up a set of stairs to a height of 9m in 30 seconds, what is the force that he must exert to get up the stairs ?

The force exerted must be 0.65N

Explanation:

Given:

Mass, m = 65 kg

Height, h = 9m

Time, t = 30 seconds

Force, F = ?

We know:

distance = speed X time

9 = s X 30

s = 0.3 m/s

Acceleration, a =

Force = mass X acceleration

Force = 65 X 0.01 N

F = 0.65N

Therefore, the force exerted must be 0.65N

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