If the object of mass 20 kg is accelerating at 0.5 m/s2, What is the net force acting on the object? 10 N
40 N
0.025 N
20.5 N

I think 0.025N

Explanation:

20 / 0.5 = 0.025

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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