Question

An object with a mass of 2 kg is moving with a velocity of 3 m/s when a 5 N net force
acts upon it. What will the object's velocity be if the force acts for 7 S?

Answer 1

By Newton's second law, the net force exerted on the object makes it undergo an acceleration a such that

(2 kg) a = 5 N

so that it is accelerated a = 2.5 m/s^2.

Since the object starts with velocity 3 m/s, after 7 s its acceleration will make it speed up to

3 m/s + (2.5 m/s^2) (7 s) = 20.5 m/s