Question 3

To determine which situation has unbalanced forces, we need to consider whether the forces acting on an object are equal and opposite or if one force is greater than the other, leading to movement.

a) **Two people pulling on the same side of a wheelbarrow** - The forces are unbalanced because both people are pulling in the same direction, potentially causing the wheelbarrow to move.

b) **A team of players in tug of war pulling on the rope, each team with equal numbers of people pulling with equal strength** - The forces are balanced because both teams exert an equal force in opposite directions, resulting in no movement.

c) **Two people on opposite sides of a big tire. One pushes the tire and one pulls it with equal force** - The forces are balanced because the pushing and pulling forces are equal and opposite, resulting in no movement.

d) **Two people not touching a crate that is sitting stationary** - There are no forces acting on the crate from the two people, hence the forces can be considered balanced (the crate is stationary due to other forces like gravity acting on it).

**Conclusion:** The situation with unbalanced forces is **(a) Two people pulling on the same side of a wheelbarrow.**