Question

Q I. Answer in one word: - (to fill the blanks)
1.Friction always ----------- motion.
2.Friction ------------- the energy of motion into heat energy and noise.
3.This instrument is used to measure friction.
4.Friction between two solid objects is often referred to as -----------.

QII. Answer in brief: -
5.What is friction? Also mention direction of friction.
6.What are the causes of friction?
7. What is asperties?

Answer 1

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1.Friction always opposes motion.

2.Friction forces the energy of motion into heat energy and noise.

3.This instrument is used to measure friction. TRIBOMETER.

4.Friction between two solid objects is often referred to as not moving relative to each other.

QII. Answer in brief: -

5. Friction is a force that opposes relative motion between systems in contact. One of the simpler characteristics of friction is that it is parallel to the contact surface between systems and always in a direction that opposes motion or attempted motion of the systems relative to each other.

6. Friction is a force that resists the relative motion between two objects or materials. The causes of this resistive force are molecular adhesion, surface roughness, and deformations.

6. An asperity is a rough portion of material. ... Large asperities can also increase the risk of corrosion. Some substances can be trapped in the recesses of the asperities.

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