# Lesson Planning of Investigating Electricity

Lesson Planning of Investigating Electricity

Subject General Science

Students` Learning Outcomes

• After studying this lesson, students will be able to:
• Make a simple electric circuit.
• Differentiate between an open and closed electric circuit.
• Distinguish between insulators and conductors.
• Identify examples of conductors and insulators in their environment.

Science Processing Skills

Observing, Classifying, Communicating, Inferring, Predicting and Experimenting.

Information for Teachers

• When a bulb is connected to a battery with the help of wires in such a way that a current flows through it, so this arrangement is called a simple circuit.

• A switch (simple) allows opening or closing a circuit and remains in the same position until we press again.
• If the circuit is open or broken, electricity can`t flow through it.

• A cell is a source of electricity. It ha two terminals, one terminal is called positive and other negative.

Close Electric Circuit:

• We have a closed circuit; it is as its name says a route through a metal cable or conductor of electricity, through which the electric current circulates. The fact that a circuit is closed comes to say that the current or electrons, goes from one side of the circuit to the other.

Open Electric Circuit:

• An open circuit is an electrical circuit in which the electric current does not circulate because it is interrupted or not communicated by means of an electrical conductor. So the current does not go through the complete circuit.
• Conductors are the materials that allow the passage of electric current, insulators prevent the passage of electricity and semiconductors are those that can behave as conductors or as insulators.

Material / Resources

Wring board, chalk / marker, duster, a connecting wire, a battery cell, wooden box, a torch bulb with a holder, textbook

Introduction

• Simple Circuit: initiate a discussion by stating one of the options:

Option 1:

• While entering home at night, we press a switch and the whole room is lighted. While going out we turn the switch off.

Option 2:

• Ask the students if they ave used a torch. When its button is pressed, it is lit. if you see its bulb, it is going. Why does it glow?
• Let us perform an activity to explore how it happens?

Material required

A torch bulb with a holder, cell and connecting wires

Method:

• Divide the class into groups of 5 each and direct them to follow the instructions given below:

1.      Insert a torch bulb in a holder.

2.      Connect the bulb with a cell using only one copper wire.

3.      Does the bulb glow?

4.      Connect two copper wires to both the terminals of the holder.

5.      Touch the free ends of the wires to opposite ends of a battery cell as shown in the figure.

6.      Does the bulb start glowing?

7.      Does the bulb glow if we remove battery cell?

8.      Why is the use of cell essentials?

9.      What do you think would happen, if we detach one wire?

10.  Detach one wire from the bulb. What do you observe?

11.  What conclusion have you drawn from this activity?

Development

Activity 1

Use of Switch

• When the switch is turned on, the circuit becomes complete or closed and the current starts flowing through it. On turning the switch off, the current is broken, so the electric current stops flowing.

Material required

A bulb with holder, cell, switch and connecting wire

Method:

• Divide the class into groups of 5 each and direct them to follow the instructions given below:

1.      Make a circuit by joining a bulb, a cell and a switch with the help of connecting wire.

2.      Turn the switch on and observe the bulb. Does it glow?

3.      Why does the bulb glow when the switch is turned on?

• In our homes, we use the switches to operate electric appliances, If the switch is off, the appliance does n`t work. Why?

Quick Quiz:

1.      What is an open circuit?

2.      What is meant by a closed circuit?

3.      What is the difference between an open and a closed circuit?

Conductors and Insulators

Activity 3

Material Required

A bulb with a holder, a cell, a switch, an iron wire, a copper wire,  a coin, a key chain, a key, a glass strip, an eraser, wooden sheet, a plastic ruler, some cotton thread and connecting wires.

Method:

• Divide the class into groups of 5 each and direct them to follow the instruction given below:

1.       Collect different material objects such as iron wires, copper wires, glass strip, eraser, aluminum sheet, wooden sheet and plastic ruler.

2.       Which material do you think will conduct electricity?

3.       Make a circuit by joining a bulb, a cell and a switch as an in activity 2.

4.       Turn the switch on. The bulb will glow which indicates that the current is flowing through the circuit.

5.       Insert one by one, the above mentioned objects in the circuit at the place of the switch and observe it.

6.       Which materials allow the bulb to glow and which ones don`t?

Sum up / Conclusion

• We have observed in the above activity that in case of closed circuit, electricity passes through the bulb, the switch and the wires. Does electricity pass through all kinds of materials which don`t let the bulb glow, can`t conduct electricity.
• The iron or copper wires and other metallic objects are conductors while the material like wood, rubber and plastic are insulators.
• When a bulb is connected to a battery with the help of wires in such a way that a current flows through it, so this arrangement is called a simple circuit.
• A switch (simple) allows opening or closing a circuit and remains in the same position until we press again.
• If the circuit is open or broken, electricity can`t flow through it.
• The materials through which electricity can pass are called conductors.
• The material through which electricity can`t pass are called insulators.

Assessment

Name three conductors.

Name three insulators.

1.       Mark () tick for true sentences and (x) for false one.

i.                  A switch is used to open or close a circuit.

ii.                 Electricity can pass through insulators.

2.       Fill in the blanks.

i.                     Electricity _____________ pass through a plastic pen.

ii.                   On turning the switch off, the circuit becomes ______ or open.

3.       What is an electric cell? What are the names of its two terminals?

4.       What is a simple circuit?

5.       For what purpose is a switch used?

6.       Name four conductors and four insulators.