Question

A basketball player can jump upwards with a velocity of 3m/s. How long is she in the air before coming back to the ground? I need the info with the units.

Answer 1

In this problem, we have an initial velocity $v_{i}=3m/s$ jump upwards (opposite direction to gravity) with the acceleration due to gravity $g=-9.8m/s^2$ , finally the player will reach to final velocity in the air $v_{f}$

Using the equation of motion, the third equation states that:

$v_{f}^{2} =v_{i} ^{2}+2gh$

where h is the height , the distance which the player reach in air

Thus

$0^{2} =3 ^{2}+2*(-9.8)*h$

$h=\frac{3^2}{2*9.8}= \frac{9}{19.6}= 0.459m$