Contact and Non-Contact Forces

Question 1

Physical cause - changes size, shape, state

Define force.

Answer 1

A force is that physical cause that changes (or tends to change) either the size, shape, or the state of rest or motion of a body.

Question 2

Name the two types of force.

Answer 2

The two types of forces are contact and non-contact forces.

Question 3

forces applied….

What are contact forces?

Answer 3

The forces that are applied on bodies by making physical contact with them are called contact forces.

Question 4

forces experienced - without being physically

What are non-contact forces?

Answer 4

The forces experienced by bodies even without being physically in touch are called non-contact forces or forces at a distance.

Question 5

Give examples of contact forces.

Answer 5

1. Frictional force
2. Normal (perpendicular) reaction force
3. Tension force as applied through strings
4. Force exerted by a spring
5. Forces exerted during collision

Question 6

Give examples of non-contact forces.

Answer 6

1. Gravitational force (force on a body due to the earth’s attraction)
2. Electrostatic force (two like charges repel and two unlike charges attract)
3. Magnetic force (two like magnetic poles repel and two unlike magnetic poles attract)

Question 7

one attracts, the other two repel + attract

their strength- distance

What are the general characteristics of non-contact forces?

Answer 7

Gravitational force is always attractive, whereas electrostatic and magnetic forces can be either attractive or repulsive. The strength of these non-contact forces depends on the distance between the bodies.