What is sliding friction?

What is sliding friction?

• A. Friction between rolling surfaces
• B. Friction due to air resistance
• C. Sliding friction
• D. Static friction

Answer: (C)

When two surfaces slide past each other, the friction that resists that motion is sliding friction. It’s a type of kinetic friction that acts opposite to the direction of movement once sliding has begun. The force depends on how hard the surfaces press together (the normal force) and how rough or sticky the surfaces are, often summarized by F = μ_k N. This is different from static friction, which prevents motion when there’s no relative movement, and from rolling friction, which occurs when objects roll rather than slide. It’s also not related to air resistance, which is drag from a fluid rather than contact between surfaces. A familiar example is pushing a book across a table: you must overcome static friction to start moving, and the friction you feel while the book slides is sliding friction.

When two surfaces slide past each other, the friction that resists that motion is sliding friction. It’s a type of kinetic friction that acts opposite to the direction of movement once sliding has begun. The force depends on how hard the surfaces press together (the normal force) and how rough or sticky the surfaces are, often summarized by F = μ_k N. This is different from static friction, which prevents motion when there’s no relative movement, and from rolling friction, which occurs when objects roll rather than slide. It’s also not related to air resistance, which is drag from a fluid rather than contact between surfaces. A familiar example is pushing a book across a table: you must overcome static friction to start moving, and the friction you feel while the book slides is sliding friction.