Question

Prequel to 10 seconds retardation equals to 2.5 metre per second height to 2495find the velocity.​

Answer 1

Intial velocity (u)=0

From t=0 to t=10(freefall)

V=0+(10)(10)

v=100m/s

Distance covered =1/2×10×10²=500m

After this retardation of a=2.5m/s²

Now from here tall it reaches ground

Distance covered =total distance -the distance covered in first 10sec =(2495-500)m=1995m

Now by 3^{rd} equation of motion

v²=u²-2as

v²=100²+(-2.5)(1995)

=10000-9975

=25

v=5m/s.

Answer 2

v²=u²-2as

=100²+(-2.5)(1995)

=10000-9975

v²=25

v=5