Question

A ball is gently dropped from a height of 20 m. If it's velocity increases uniformly at the rate of 10 m/s², with what velocity will it strike the ground? After what time will it strike the ground?

Answer 1

Given that,
Distance(s)="20m"
Initial velocity(u)=0m/s
Accelaration="10m/s-2"

Using the relation Distance-Time

s=v2 - u2=2a

s= v2-0=2*10
20=v2-0=20
v2-0=20*20
v2=400(underoot)
v=20 m/s

time=v=u=at
20=0+10
20 upon 10=0+10(t)=
time= 2 secs