Question

A stone is thrown into the air with initial speed of 3m/s from the ground.

What time does it hit the ground? (Neglect air resistance)

Answer 1

The time elapsed as a stone was thrown and it hit the ground

$$\Delta t=2\times \frac{v_0}{g}\\ =\rm 2\times\frac{3.0\: m/s}{9.8\: m/s^2}=0.61\: s$$