When balanced forces act on an object, what type of motion can the object have?

A.

It can only be motionless.

B.

It can move only at a constant speed in a straight line.

C.

It can be motionless or move at a constant speed in a straight line

Answer: A. It can only be motionless.

Explanation: When balanced forces act on an object, the object will not move. The only way that object can move is if the forces become unbalanced. Suppose there is a shoe on a table. You are pulling back on the shoe with a force of 3 newtons. But the friction from the shoe rubbing on the table is also 3 newtons of force. But the gravity pulling down on the shoe is also 3 newtons. Nothing will move. The only way the shoe can move is if you pulled with a little more force. The shoe would then move because the force you are pulling with is greater than the other forces acting on the shoe.

Ex 2: You are playing tug of war. Team a is pulling with 20 Newtons of force. Team b is also pulling with 20 newtons of force. The rope does not move. Team a starts to pull a little harder. Now they are pulling with 25 Newtons of force. Now the rope starts moving their way.