A skydiver slows down from 65 m/s to 5 m/s by opening the parachute. If this takes 0.75 seconds, what is the skydiver's acceleration?
A. 45 m/s2 up
B. 80 m/s2 up
C. 45 m/s2 down
D. 80 m/s2 down

Explanation:

We are asked to find the acceleration of a skydiver. Acceleration is the change in velocity over the change in time, so the formula for calculating acceleration is:

The skydiver was initially traveling 65 meters per second, then he slowed down to a final velocity of 5 meters per second. He slowed down in 0.75 seconds.

Substitute the values into the formula.

Solve the numerator.

Divide.

The acceleration of the skydiver is -80 meters per second squared or 80 meters per second squared down. The skydiver is slowing down or decelerating, so the acceleration is negative or down.

the answer is b. dilution