Which example shows unbalanced forces acting on an object?

Question

A. Two people are on opposite sides of a large box. Both people push the box with equal force.
B. Two people are on the same side of a large box. Both people pull the box with equal force.
C. Two people are on opposite sides of a large box. Both people pull the box with equal force.
D. Two people are on the same side of a large box. One person pushes the box and the other pulls the box with equal force.

Answer 1

The example that shows unbalanced forces acting on an object is:

D. Two people are on the same side of a large box. One person pushes the box and the other pulls the box with equal force.

In this scenario, the two forces (one pushing and one pulling) act in opposite directions but are equal in magnitude, which means they do not cancel each other out completely, resulting in unbalanced forces and causing the box to move in the direction of the net force.