Question

A stone piece is just dropped from a height of 180 m.lf its velocity increases uniformly at the rate of 10ms-2 , with what velocity will it strike the ground? how much time does the stone take to reach the ground

Answer 1

time=√2h/g
=√2×180/10
=√2×18
=√36
=6
final velocity of stone =√2gh
=√3×10×180
=√3600
=60m/s
these two formulas help in many entrance exam so remember these formulas.
But remember these formulas are apply in freely falling body only. Not use in linear motion.
Hope it helps you..........

Answer 2

s=180m a=10m/s^2 u=0 find v
v^2=u^2+2as
v^2=0+2(10)(180)
v^2=3600
v=60

The stone piece will strike the ground with velocity of 60m/s.

v=u+at
60=0+(10)t
t=6s 

The stone took 6seconds to reach the ground.