Question

A skydiver free falls from rest. How long does it take for the skydiver to reach 7 m/s?

Answer 1

Answer:

The skydiver needs 0.71 seconds to reach 7 m/s

Explanation:

Free Fall Motion

When an object is dropped in free air (no friction) from a certain height h, it follows a free-fall motion, whose acceleration is due exclusively to gravity. The speed at a moment t when the object is dropped (from rest) is:

$V_f=gt$

We need to find How long does the skydiver needs to reach 7 m/s. We solve for t

$\displaystyle t=\frac{V_f}{g}$

$\displaystyle t=\frac{7}{9.8}$

$t=0.71\ sec$

The skydiver needs 0.71 seconds to reach 7 m/s