Question

A ball is projected upwards from a height h above the surface of earth with velocity v. The time at which the ball strikes the ground is

Answer 1

Vector format let height be =-h
Velocity in upward direction be =+v
And acc=-g (downward)
Now putt everything in eq h=vt+1/2gt^2 along with sign
So, -h =vt-1/2gt^2
Solve this to get time...