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:
[tex]V_f=gt[/tex]
We need to find How long does the skydiver needs to reach 7 m/s. We solve for t
[tex]\displaystyle t=\frac{V_f}{g}[/tex]
[tex]\displaystyle t=\frac{7}{9.8}[/tex]
[tex]t=0.71\ sec[/tex]
The skydiver needs 0.71 seconds to reach 7 m/s
