Question

A ball of mass 1 kg is dropped from a height of 5m. (a)find the kinetic energy of ball just before it reaches the ground . (b) What is its speed at this instant.ii

Answer 1

K.E= p.e=mgh

= 1×10×5

=50J

Also, k.e=1/2mv×v

50J =1/2×1×v×v

50×2=v×v

100=v×v

√100=v

10m/s=v