Question

A particle is projected from ground in a vetical direction at t=0 sec. at t=0.8 s, it reaches h=14m .It will again come to the same height at ?

Answer 1

h= v₀•t-g•t²/2 ,
v₀=h/t +gt/2 = 14/0.8 +9.8•0.8/2 = 21.42 m/s.
Time of the motion to the highest point
t₀=v₀/g =21.42/9.8=2.19 s.
t1=2•2.19 – 0.8=3.58 s.

Answer 2

Can we use 10 meter per second square instead of 9.8 meter per sec square