Question

An object is thrown to a certain height with a velocity of 3 m/s. If the time required to reach the height is 5s. Calculate the height at which it was thrown. [Hint: (g=10m/s^2) (use second equation of motion)]

Answer 1

If it reaches the ground

It's displacement is 0

A =-10m/s^22

U=100m/s

S=ut+1/2at^2

0=100t-5t^2

5t^2=100t

5t=100

t=100/5

t=20s

The ball will reach the ground in 20s

Hope this helps:

Thank you.