Question

which of these statements describe friction? check all that apply.
□ friction allows objects to slide over each other without any resistance.
□ friction resists motion.
□ friction is a force that acts from a distance.
□ friction is a contact force.
□ friction is caused by microscopic bumps and ridges on surfaces.

Explanation:

• Friction opposes relative motion between surfaces, so it resists motion.
• Friction only occurs when two surfaces are in direct contact, making it a contact force (not a force acting from a distance).
• The microscopic irregularities (bumps/ridges) on surfaces interlock, which is the physical cause of friction.
• The first statement is incorrect because friction creates resistance to sliding, not allows it without resistance.

Answer:

• Friction resists motion.
• Friction is a contact force.
• Friction is caused by microscopic bumps and ridges on surfaces.