What force resists the motion of one surface relative to another?

What force resists the motion of one surface relative to another?

• A. Gravitational force
• B. Normal force
• C. Friction
• D. Applied force

Answer: (C)

Friction is the force that resists the relative motion of two surfaces in contact. When an object tries to slide across another surface, friction acts in the opposite direction to the motion, providing resistance. This force occurs due to the interactions at the microscopic level between the surfaces in contact, where surface roughness and adhesive forces play a significant role. In practical terms, if you push an object across a surface, the frictional force will act to slow down the object and prevent it from sliding indefinitely. This is essential in everyday situations, such as walking, driving, or any activity involving the movement of objects. Other forces like gravitational force act downwards in the context of weight, the normal force acts perpendicular to the surface, and the applied force is the force exerted on an object. While these forces are important in different scenarios, they do not specifically describe the resistance to motion between two surfaces, which is the role of friction.

Friction is the force that resists the relative motion of two surfaces in contact. When an object tries to slide across another surface, friction acts in the opposite direction to the motion, providing resistance. This force occurs due to the interactions at the microscopic level between the surfaces in contact, where surface roughness and adhesive forces play a significant role.

In practical terms, if you push an object across a surface, the frictional force will act to slow down the object and prevent it from sliding indefinitely. This is essential in everyday situations, such as walking, driving, or any activity involving the movement of objects.

Other forces like gravitational force act downwards in the context of weight, the normal force acts perpendicular to the surface, and the applied force is the force exerted on an object. While these forces are important in different scenarios, they do not specifically describe the resistance to motion between two surfaces, which is the role of friction.