Which of the following forces can only be applied when in contact with an object?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e. Frictional force.
Frictional force is a type of contact force that can only be applied when there is physical contact between two surfaces. It acts parallel to the surfaces in contact and opposes the relative motion or tendency of motion between them. This force is crucial for tasks like walking, driving, and gripping objects. Without contact, frictional force cannot exist, as it relies on the interaction between surfaces to generate resistance and prevent slipping or sliding. Thus, frictional force is inherently a contact force.