Question

A 2kg object is moving horizontally with a speed of 4 m/s. How much net force is required to keep the object moving at this speed and in this direction

Answer 1

We can solve this problem using the force equation.

Force = Mass * Acceleration

2kg * 4m/s = 8 N

The net force required to keep the object moving at this speed and in this direction is 8 N.

Answer 2

Answer: F = 0, if you apply a force, the velocity of the object may change.

Explanation: If there is no force of friction or something like that, there is no actual force applied to the object, because it has not any acceleration. This means that the object reached an uniform motion state, this means that the object will move with the constant velocity until a force is applied over it. This is because if there is no force applied, there is no acceleration (by the second Newton's law, we have that F = m*a) and the acceleration is the rate of change of the velocity, so if there is no acceleration, there is no change in the velocity.

This means that the net force required to keep the object moving at 4m/s and un the same direction is zero; F = 0