Final answer:
The scenarios of a cat sleeping in a chair and a mug resting on a bench both depict situations with balanced forces, as the objects are at rest and the force of gravity and the normal force are equal and opposite.
Step-by-step explanation:
The question asks us to identify which situations involve balanced forces. Balanced forces occur when the total force on an object is zero, resulting in the object either being at rest or moving with a constant velocity. In the scenarios presented:
- A cat sleeping in a chair - the cat is at rest and the forces acting on it, including gravity and the normal force from the chair, are in balance.
- A bike turning a corner - the bike is changing direction, which means there is a net force causing this change, so the forces are not balanced.
- A mug resting on a bench - the mug is at rest, with gravity pulling it down and the bench providing an equal and opposite force upwards, indicating balanced forces.
- A rollercoaster slowing down as it moves up a slope - there is a net force acting on the rollercoaster causing it to decelerate, namely gravity, so the forces are not balanced.
Therefore, the situations involving balanced forces are:
- A cat sleeping in a chair
- A mug resting on a bench