Question

a body of mass 2Kg starts from rest and moves with uniform acceleration. It acquires a velocity 20ms in 4s. The power exerted on the body in 2s in watt is

Answer 1

P=W/T
m=2kg
u=0m/s
v=20m/s
t=4s
a=(v-u)/t
 =20/4 =5m/s^2
W=F=ma
ma=2*5
      =10N
P=10/2
   =5watt