Question

A body of mass 2kg starts from rest and moves with uniform acceleration. It acquires a velocity 20m/s in 4s. The average power exerted on the body in 2s is
1)50W
2)100W
3)150W
4)200W

Answer 1

200W is the answer

hope it's correct

Answer 2

m=2 kg

u= o m/s

v= 20 m/s

t= 4 s

so, acceleration = (v-u)/t

= 20/4

= 5 m/s^2

therefore, force= 2×5=10 N

s= 1/2 at^2

= 1/2×5×16

= 40 m

so, work = force×displacement

= 10×40

= 400 j

therefore, power = work /time

= 400/2

= 200 watt