Final answer:
Yes, forces can act on an object in any direction even if it is at rest, as they can be balanced with no net force acting on the object. In uniform circular motion, a net force must act on the object because it is accelerating towards the center. Forces in equilibrium on a point have equal magnitudes but opposite directions.
Step-by-step explanation:
Can there be forces acting on an object if the object is at rest? The answer is d) Yes, forces can act in any direction. An object at rest may still be subjected to multiple forces, but if the object remains stationary, it implies that all the forces are balanced, resulting in no net force. For example, a book lying on a table is subjected to gravitational force pulling it downwards and an equal magnitude of normal force exerted by the table pushing it upwards.
When discussing uniform circular motion, 'Is there a net force acting on an object in uniform circular motion?' the correct answer is a) Yes, the object is accelerating, so a net force must be acting on it. Despite moving at a constant speed, the object is constantly changing its direction, which means it is accelerating, thereby necessitating a net force towards the center of the circle, often referred to as centripetal force.
To answer 'A point is acted on by two forces in equilibrium', the correct response is b) have equal magnitudes but opposite directions. This implies that the object is either at rest or moving at a constant velocity due to the balanced (equilibrated) forces.