Answer:
5.7 seconds
Explanation:
1. We know that :
acceleration = change in velocity / time
2. We have been given the following :
acceleration = - 3.7 m/s^2
initial velocity = 21.1 m/s
final velocity = 0 (at the rock's max greatest height its velocity is 0)
time = ?
3. Subsitute the values + rearrange for t :
-3.7 = 0 - 21.1/t
t = 0-21.1/-3.7
t = -21.1/-3.7
t = 5.7 seconds (1.d.p)
