# CONTACT AND NON CONTACT FORCE

Class :

JSS 1 / Basic 7

Subject :

Basic Science and Technology

Topic :

FORCES

Term : Third Term

Week : Week 3

Instructional Materials :

• pictures of students that are trying to open a supermarket  door with the inscription of pull or push
• learners are made to push heavy objects in the classroom like the book case or the cupboard

Reference Materials

• Scheme of Work
• Online Information
• Textbooks
• Workbooks
• 9 Year Basic Education Curriculum

Previous Knowledge :

The pupils have previous knowledge of

Effects of Pollution

which was the topic that was taught during the last lesson

Behavioural Objectives :  By the end of the lesson, the learners should be able to

• explain force
• describe the force of pull and push
• say the difference between pull and push
• Distinguish between contact force and force of gravity.
• Explain the magnetic force.

WEEK THREE

FORCES

A force can be defined as any action that makes or tries to move, stop or alter the speed of a body in a given direction.

TYPES OF FORCE

There are two types of force namely:

1. Contact force

2. Non-contact

CONTACT FORCE

These are forces which sources are in contact with the body to which they are applied. The contact forces could be direct or indirect. Examples of contact forces are; Push, Pull ,Tension, Friction, Upthrust.

NON- CONTACT FORCES

These are forces which the sources do not require contact with the body they are applied. These forces act through a region in space called field. They are therefore also called FORCE FIELDS. Example include: Gravitational force, Electric force, Magnetic force

MAGNETIC AND GRAVITATIONAL FORCES

In a bar magnetic, there is North pole end south pole end, the like poles repel each other while unlike poles attract each other. Two magnets can attract each other when they were still some distance apart. Also magnet can attract iron fillings before the magnet came in contact with the iron fillings. These magnets came in contact with the iron fillings. This phenomenon shows that magnetic force act over an area around the magnet. Thus a magnetic force is called a field force which acts over an area.

GRAVITATIONAL FORCES

The force by which the earth attracts all objects to itself is called the force of gravity or gravitational force. This is the reason why objects above the earth fall down to the earth.

The light objects like feathers, children balloon which do not fall immediately to the earth are supported by air, but they eventually fall to the earth.

Presentation

The topic is presented step by step

Step 1:

The class teacher revises the previous topics

Step 2.

He introduces the new topic

Step 3:

The class teacher allows the pupils to give their own examples and he corrects them when the needs arise

EVALUATION

1. Explain the magnetic force.

2. What do you understand by gravitational force ?

GENERAL EVALUATION

1. Explain the magnetic force.
2. What do you understand by gravitational force?
3. Distinguish between contact force and force of gravity
4. How would you demonstrate a magnetic force?
5. Name two contact and two non-contact forces.

WEEKEND ASSIGNMENT

1. Which of the following statement is false A. a force changes the shape of a body

B. forces may be balanced or unbalanced C. a force cannot change the direction of a moving body D. a force changes the speed of object

2. Which of the following is not a type of force? A. electrical B. contact C. magnetic D. reversible

3. When a canoe – man paddles backwards in the water, the canoe moves forward this shows that A. forces occur in pair B. contact force is acting C. a force is not involved D. water is pushing the canoe.

4. The gravitational force can be found A. on the earth B. in the moon C. around the planets D. in the galaxy

5. The magnetic force is also known as ___ A. pulse B. electrical C. field force

D. gravitational force

THEORY

1. Distinguish between contact force and force of gravity.

2. How would you demonstrate a magnetic force?

3. Name two contact and two non-contact forces.

Conclusion :

The class teacher wraps up or conclude the lesson by giving out short note to summarize the topic that he or she has just taught.

The class teacher also goes round to make sure that the notes are well copied or well written by the pupils.

He or she does the necessary corrections when and where  the needs arise.

Assignment :