# Basic Science Guides for JSS 1 You and Energy – Energy, Force and Renewable and Non Renewable Energy

BASIC SCIENCE

THEME – YOU AND ENERGY

#### TOPIC 1 – ENERGY

INSTRUCTIONAL MATERIALS

1. Samples of coal

2. Crude oil

3. Gas

4. Chart of the sun

5. Battery

6. Torch light

7. Turning fork

8. Chart showing a moving car, cooking food, electrical heater, torch light, etc.

LEARNING OBJECTIVES

By the end of the lesson, students should be able to:

1. explain the meaning of energy.

2. state and describe the sources of energy.

3. name forms of energy.

4. explain how energy is transferred from one form to another.

5. state the uses of energy.

### FOCUS LESSONS

#### A. Introduction

Energy is the fundamental need of our everyday life.

Energy is everywhere around us and takes different forms.

For examples,

• It can be felt as heat.
• It is observed with eyes as light.
• kinetic energy is perceived as force.

The quality of life and even its sustenance, is dependent on the availability of energy.

For example, it takes energy to cook food, to drive to school, and to jump in the air, etc.

B. Meaning of Energy

Energy is the ability of a body to do work.

Work is said to be done when applied force moves a body through a given distance.

Energy is neither created nor destroyed.

Energy is converted from one form to another.

#### C. Sources of Energy

1. Plant and animals

2. Sun

3. Water

4. Electrical

6. Machine

7. Fuel

8. Coal, etc.

#### D. Forms of Energy

The forms of energy are as follows:

1. Kinetic energy

2. Potential energy

3. Solar energy

4. Light energy

5. Heat enegy

6. Electrical energy

7. Mechanical energy

8. Chemical energy

9. Sound energy

1. KINETIC ENERGY

Kinetic energy is an energy in motion.

It is actively using energy for movement.

For examples,

• Walking
• Running
• Falling
• Throwing a ball
• Flying aeroplane

2. POTENTIAL ENERGY

Potential energy is the energy stored in a person or object as a result of its position.

When potential energy is released, it becomes kinetic energy.

For examples,

• The food we eat
• An orange on a tree branch
• Air in a balloon before it is released
• A child at the top of a slide
• A bottle on a table before it falls

3. SOLAR ENERGY

Solar energy is the energy that comes from the sun.

For examples,

• Light
• Heat

4. LIGHT ENERGY

Light energy is the energy that makes us to see things clearly.

For examples,

• Sun, moon and star
• Light bulb
• Firefly
• Torchlight
• Candle
• Computer screen
• Firewood light
• Lighting
• Traffic light, etc.

5. HEAT ENERGY

Heat energy is an energy transfer between two or more objects.

For examples,

• The heat from the sun
• A cup of hot tea
• Baking in an oven
• The heat from a pressing iron

6. ELECTRICAL ENERGY

Electrical energy is an energy from electric charger participles.

For examples,

• Electricity generators
• Batteries
• Hydropower
• Power generating plants

7. MECHANICAL ENERGY

Mechanical energy is the sum of potential and kinetic energy.

For examples,

• Human body
• Wind
• Tide
• Breathing in and out
• Hammering a nail
• Riding a bicycle, etc.

8. CHEMICAL ENERGY

Chemical energy is the energy from chemical reactions between atom or molecules.

For examples,

• Food
• Batteries
• Kerosene
• Petrol
• Coal, etc.

9. SOUND ENERGY

Sound energy is the energy that we can hear.

For examples, energy from radio, television, musical instruments are known as sound energy.

#### E. Transfer of Energy

The change of energy from one form to another is known as energy transfer.

According to the first law of thermodynamics, energy can be neither created nor destroyed.

In other words, energy is the only thing that is constant in the universe.

#### F. Uses of Energy

The uses of energy are as follows:

1. It is used for boiling water.

2. It used used for producing light.

3. It is used for entertainment.

4. It is used for cooking.

5. It is used for working.

6. It gives us strength.

7. It makes vehicles go, planes fly, boats sail, and machines run.

LESSON PRESENTATION

TEACHER’S ACTIVITIES

The teacher:

1. initiates discussion.

2. leads students to mention sources of energy.

3. provides some materials for activities to illustrate forms of energy

4. uses the activities in (3) to illustrate transfer.

5. Provides charts on uses of energy ford.

STUDENT’S ACTIVITIES

The students,

1. participate in discussion

2. mention sources of energy.

3. carry out activities on energy.

4. describe the actions as indicated on the chart.

LESSON EVALUATION

1. explain the meaning of energy.

2. state three sources of energy and describe two of them.

3. state four forms of energy.

4. explain the energy transfer in the following: kicking a ball, striking a match, heating water.

5. state four uses of energy.

BASIC SCIENCE

THEME – YOU AND ENERGY

#### TOPIC 2 – FORCE

INSTRUCTIONAL MATERIALS

1. Fixed door paper, spring, rubber

2. Charts showing contact and non-contact forces

3. Objects of known mass, meter-rule Newton-meter

4. Knife edge and slotted weights

5. Toy car, cardboard paper, rough surface.

LEARNING OBJECTIVES

By the end of the lesson, students should be able to:

1. explain the concept of force.

2. identify contact and non-contact forces.

3. differentiate between magnetic and gravitational forces.

4. measure and calculate gravitational force when mass and height are provided.

5. demonstrate balance and unbalanced forces.

CONTENTS OF THE LESSON

FOCUS LESSONS

#### A. Concept of Force

A force is the power that makes an object to move by pushing or pull.

It opposed movement of an object or caused an object to move.

For example, car acceleration and break are good examples of push and pull forces.

#### B. Types of Forces

There are many types of forces, but only five are discussed below:

1. Muscular Force

2. Gravitational Force

3. Magnetic Force

4. Electrical Force

5. Frictional Force

1. MUSCULAR FORCE

Muscular force is the force applied to an object using the parts of body such as arms and legs.

For example – weight lifting (hands) and riding a bicycle (legs).

2. GRAVITATIONAL FORCE

Gravitational force is force that pulls an object down to earth.

3. MAGNETIC FORCE

Magnetic force is the force that attracts all magnetic materials to itself or push them further away from itself.

It is also pull or push force.

4. ELECTRICAL FORCE

Electrical force is the force that produces electric current.

5. FRICTIONAL FORCE

Frictional force is the force that opposed or slow movement.

6. BALANCE AND IMBALANCE FORCE

Balance force is the force that keep an object to rest while imbalance force is the force that makes an object to move from one place to another.

7. CONTACT AND NON CONTACT FORCE

Contact force is the force that is applied directly to an object while non contact force is the force that attracts objects from a distance.

#### D. Effects of Force

A force acting on an object may cause the object:

1. to change shape and size.

2. to start moving.

3. to stop moving.

4. to rotate.

5. to accelerate or decelerate.

#### E. Introduction of Friction

To stop a moving object, a force must act in the opposite direction to the direction of motion.

For instance, if you push your book across your desk, the book will move. The force of the push moves the book.

As the book slides across the desk, it slows down and stops moving.

The force that opposes the motion of an object is called friction.

#### F. Meaning of Frictional Force

Friction is the force that opposes the motion of an object.

Friction can slow down or stops any moving objects.

Friction plays a vital role in our daily life.

Without friction we are handicap.

#### G. Effects of Frictional Force

The effects of the frictional force on objects are as follows:

1. It opposes the motion of all objects.

2. It slow down any moving objects.

3. It counteracts the acceleration of an object.

4. It prevents surfaces from sliding against each other.

5. It causes objects to accelerate.

The advantages of friction are as follows:

1. It prevents slipping while walking.

2. It stops cars from moving.

3. We cannot fix nail in the wood or wall if there is no friction.

It is friction which holds the nail.

4. A horse cannot pull a cart unless friction furnishes him a secure Foothold.

Despite the fact that the friction is very important in our daily life, it also has some disadvantages such as,

1. The main disadvantage of friction is that it produces heat in various parts of machines.

In this way some useful energy is wasted as heat energy.

2. Due to Friction, we have to exert more power in machines.

3. It opposes the motion.

4. Due to friction, noise is also produced in machines.

5. Due to friction, engines of automobiles consume more fuel which is a money loss.

#### J. Methods of Reducing Friction

There are a number of methods to reduce Friction,

1. The use of lubricants

2. The use of grease

3. The use of ball

4. The design modification

1. THE USE OF LUBRICANTS

The parts of machines which are moving over one another must be properly lubricated by using oils and lubricants of suitable viscosity.

2. THE USE OF GREASE

Proper greasing between the sliding parts of machine reduces the friction.

3. THE USE OF BALL

Bearing In machines where possible, sliding friction can be replaced by rolling friction by using ball bearings.

4. THE DESIGN MODIFICATION

Friction can be reduced by changing the design of fast moving objects. The front of vehicles and airplanes made oblong to minimize friction.

LESSON PRESENTATION

TEACHER’S ACTIVITIES

The teacher,

1. guides students to push and pull, squeeze, bend and stretch objects.

2. provides chart showing contact and non-contact forces.

3. guides students to calculate gravitational force using the formula GF = mgh.

4. guides students to set up balanced and unbalanced forces.

5. provides materials and direct illustration of frictional forces.

STUDENT’S ACTIVITIES

The students,

1. carry out activities as directed by teacher e.g. push and pull.

2. identify contact and non-contact forces.

3. carry out activity and calculate GF.

4. practice setting up balanced and unbalanced forces.

5. illustrate frictional force between objects, noting advantages and disadvantages of friction.

LESSON EVALUATION

1. explain the concept of force.

2. name two contact and two non-contact forces.

3. state the differences between magnetic and gravitational forces.

4. describe how to determine the gravitational force of an object at a given height. Use GF=mgh for calculation.

5. describe how to set up a balanced force.

6. explain the meaning of friction and state two uses and disadvantages of friction.

BASIC SCIENCE

THEME – YOU AND ENERGY

#### TOPIC 3 – RENEWABLE AND NON RENEWABLE ENERGY

INSTRUCTIONAL MATERIALS

1. Charts showing renewable and non-renewable energy.

2. Charts or pictures of renewable solar plates, windmill, hydroelectric source.

3. Samples of non-renewable energy (coal, crude oil, wood, gas).

4. Chart on bunkering, felling of trees, electronic equipment repair.

LEARNING OBJECTIVES

By the end of the lesson, students should be able to:

1. explain the meanings of renewable and non-renewable energy.

2. give examples of renewable and non-renewable energy.

3. state the implications of misuse of non-renewable energy.

4. describe how energy generation affects quality of life.

CONTENTS OF THE LESSON

FOCUS LESSONS

#### 1. Renewable and Non Renewable Energy

• meaning
• examples
• use and misuse.

#### 2. Energy and Society

LESSON PRESENTATION

TEACHER’S ACTIVITIES

The Teacher,

1. initiates and leads discussion on renewable and non-renewable energy.

2. leads the discussion to identify renewable and non-renewable energy.

3. leads discussion on conservation of crude oil, felling of most trees in the forest, overloading the hydroelectric power stations etc.

STUDENT’S ACTIVITIES

The students,

1. participate in the discussion.

2. identify renewable and non-renewable energy.

3. participate in the discussion and note the main ideas.

LESSON EVALUATION

1. explain the meanings of renewable and non-renewable energy.

2. give 3 examples each of renewable and non-renewable energy.

3. state one effect of the wrong use of non-renewable energy.

4. state three reasons for careful use of coal or petroleum products.

5. state three ways through which lack of energy supply affects societal development.