In physics, unbalanced forces occur when the net force acting on an object is not zero. Let’s analyze each of the situations you provided to determine which involves unbalanced forces:
A. Two people stand on the same side of a large tire, both people pulling the tire with equal force.
- Here, the forces are equal and in the same direction, resulting in a net force that is not zero. This means that the tire will move in the direction they are pulling.
B. Two people standing on the same side of a large tire, one person pushes the tire and the other pulls the tire with equal force.
- In this case, one force is pulling, and the other is pushing. These forces act in opposite directions and are equal, resulting in a net force of zero. Therefore, the tire will not move.
C. Two people stand on opposite sides of a large tire, both people push the tire with equal force.
- Similar to situation A, both individuals are applying forces in the same direction, meaning there is a net force in that direction. The tire will move in the direction they are both pushing.
D. Two people stand on opposite sides of a large tire, both people pull the tire with equal force.
- This situation is like situation B; although both are pulling, they are doing so in opposite directions with equal force. Therefore, the net force is zero, and the tire will not move.
Conclusion: The situations where unbalanced forces act on the tire are A and C.