# physics

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ursula and her 2 year old daughter unice descend a flight of stairs 10 m high, if ursula carries unice and their combined mass is 75 kg and reach the ground in 8 seconds. compute for
a.) work done in going down
b.) power developed by ursula in going down

• physics -

a) W = -M g H

b) P = -M g H/t

The minus sign means gravity does work on Ursula, going down the stairs.

M = 75 kg
g = 9.8 m/s^2
H = 10 m
t = 8 s
P is in Watts

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