Answer:
200 m/s
Explanation:
as momentum is a product of mass and speed, and mass is not changing, four times the speed will result in four times the momentum.
p = mv
4p = m(4v)
Acceleration = (change in speed)/(time for the change)
Change in speed = (end speed) - (start speed)
Change in speed = (10 m/s) - (20 m/s) = -10 m/s
Time for the change = 5.00 seconds
Acceleration = (-10 m/s) / (5 sec)
<em>Acceleration = -2 m/s²</em>
That's choice-A .
A. gravity is your answer hope this helps