Short Answer Questions
1. Define:
a. Contact force
b. Force of friction
2. Give two examples of friction related to our daily life.
3. How application of lubricants helps in reducing friction?
4. Why airplanes are streamlined in shape?
5. How friction causes wear and tear of machines?
Answers
Answer:
1)
A contact force is any force that requires contact to occur. Contact forces are ubiquitous and are responsible for most visible interactions between macroscopic collections of matter. Pushing a car up a hill or kicking a ball across a room are some of the everyday examples where contact forces are at work
2)
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. There are several types of friction: Dry friction is a force that opposes the relative lateral motion of two solid surfaces in contact
3)
Rubbing both hands together to create heat.
A sled sliding across snow or ice.
4)
Fast-moving vehicles are given streamline shape as their streamlined shape cuts through the air very easily and thus increased their speed. The streamlined shape is given to aeroplanes in the air and ships in the water to reduce the fluid friction
5)
Friction erodes the show leather and the base over the period of time. ... Friction is basically a force that results in resisting of the relative motion of tough surfaces or, fluid layers, and material elements by sliding against each other.
Explanation:
Hope it helps you