A net force of 10 N accelerates an object at 5.0 m/s2. What is the net force required to accelerate the same object at 1.0 m/s2?

Answer 1

one-fifth the acceleration, so one-fifth the force. (assuming that the object's mass doesn't change.)

Answer 2

2N

(but they make me write a 15-character answer)

Answer 3

f=ma

so it's proportional in all cases