Science Class 7 - Electric Current-And-Its-Effects Notes

Electric Current and Its Effects

Welcome to the chapter on Electric Current and Its Effects for Class 7. In this chapter, you will learn what electric current is, how it flows, and the effects it can produce. By the end of this chapter, you will understand how electric circuits work and how electricity is used in daily life!

Introduction

Electric current is the flow of electricity through wires and circuits. It helps us light bulbs, run fans, and use many devices at home and school.

What is Electric Current?

• Electric current is the movement of electric charge (usually electrons) through a conductor like a wire.
• It needs a source, such as a battery or cell, to flow.

Electric Circuits

An electric circuit is a path through which electric current flows. It usually has a source (battery), wires, and a device (like a bulb).

• A circuit must be complete (closed) for current to flow.
• If the circuit is broken (open), the current stops.

Effects of Electric Current

• Heating Effect: Electric current can heat things, like in an electric heater or bulb.
• Magnetic Effect: Electric current can create a magnetic field, used in electromagnets and electric bells.
• Chemical Effect: Electric current can cause chemical changes, like in batteries and electroplating.

Uses of Electric Current

• Lighting bulbs and tube lights
• Running fans and machines
• Operating computers and TVs
• Charging mobile phones
• Electroplating and welding

Safety with Electricity

• Never touch electric wires with wet hands.
• Do not play near electric poles or sockets.
• Always switch off appliances when not in use.
• Call an adult or electrician for repairs.

Fun Activity: Make a Simple Circuit

Take a battery, a bulb, and two wires. Connect them to make the bulb glow. Try opening and closing the circuit to see what happens!

Summary

• Electric current flows through circuits and wires.
• It can produce heat, magnetism, and chemical changes.
• Electricity is useful but must be handled safely.

Practice Questions

1. What is electric current?
2. Name two effects of electric current.
3. What is needed for current to flow in a circuit?
4. Why should we be careful with electricity?
5. Give one example of the magnetic effect of electric current.

Challenge Yourself

• Draw and label a simple electric circuit.
• List three devices at home that use electric current.

Did You Know?

• Lightning is a natural form of electric current!
• Electric current can travel very fast—almost at the speed of light!

Glossary

• Electric Current: Flow of electricity through wires.
• Circuit: A path for electric current.
• Conductor: Material that allows current to flow (like copper wire).
• Insulator: Material that does not allow current to flow (like plastic).

Answers to Practice Questions

1. It is the flow of electric charge through a conductor.
2. Heating effect, magnetic effect (also chemical effect).
3. A complete (closed) circuit and a source like a battery.
4. Because it can be dangerous and cause shocks or fires.
5. Electromagnet or electric bell.

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Learn about electric current and use electricity safely every day!