Question

13 question

Define Power Two girls A and B each of weight 50Kg climb up a rope through a height of 10 m . Girl A takes 20s whereas B takes 50 s to accomplish. This task calculate the power expended by each girl.

Answer 1

Power is defined as energy consumed or work done per unit time its SI unit is watts or joules/ sec​

2nd part:-

For girl A,
Weight of the girl, W= mg = 400 N
Distance travelled, h = 10 m
Time taken, t = 20 s
Using equation,
Power (P) = Work done (W) ⁄ time taken(t)
P= mgh /t
=400 x 10 /20
=200 W
For girl B,
Weight of the girl, W= mg = 400 N
Distance travelled, h = 10 m
Time taken, t = 50 s
P=W/t=mgh/t
=400 x 10 /50
=80 W
Power expended by girl A is 200W.
Power expended by girl B is 80 W.