Newton’s First Law of Motion states that an object at rest stays at rest, and an object in motion stays in motion unless acted on by an unbalanced force. Among the statements that describe this law, option A, ‘an object must be at rest before a force can act on it,’ is incorrect.
The law emphasizes that the state of motion of an object will not change unless a net force is applied. This means that even if an object is in motion, it will continue moving indefinitely in a straight line at a constant speed unless something disrupts that motion. It’s important to understand that the law applies to both stationary and moving objects.
This principle highlights the concept of inertia, which is the tendency of an object to resist changes in its state of motion. Therefore, objects can be in two states: at rest or in motion. But crucially, they do not need to be at rest to experience a force. Forces can act on moving objects just as well, altering their speed or direction.