Question

7. A man weighing 100 kg and running on
a track wants to increase his speed from
8 ms-1 to 10 ms-1. Find the minimum time in
which he can do this if the maximum power
is 900 W.
(Ans. 1.2 s)​

Answer 1

Answer:

REF.Image

Let us take, the normal

reaction extorted by

man on the load be 'N'

since, the load has downward acceleration of 'g'

Applying Newton's II law of motion (F

net

=ma)

⇒10g−N=10×g

⇒N=0

Since, the normal reaction on the load is zero

⇒ the man will experience no weight of

the load i.e. zero weight.