Magnetism Unleashed Through Current and Electromagnets

The video explains how a conductor carrying current behaves like a magnet, known as an electromagnet. It demonstrates an activity using a wire, iron nail, and battery to create an electromagnet. The video also highlights the uses of electromagnets in cranes, material separation, and electric bells. It further details the working of an electric bell, where an electromagnet attracts a soft iron strip to produce sound, illustrating the concept of electromagnetism in practical applications.

What happens when current flows through a conductor?

• It loses its conductivity.

• It changes color.

• It heats up.

• It becomes a magnet.

In the activity, what role does the iron nail play?

• It acts as a battery.

• It becomes an electromagnet.

• It provides insulation.

• It is used to complete the circuit.

What is an electromagnet?

• A coil that acts as a magnet when current flows through it.

• A permanent magnet.

• A device that stores electrical energy.

• A magnet that works without electricity.

Which of the following is NOT an application of electromagnets?

• Generating electricity in power plants.

• Separating magnetic materials from scrap.

• Operating an electric bell.

• Lifting heavy loads with cranes.

How does the electric bell produce sound?

• By using a permanent magnet.

• By vibrating a metal strip.

• By striking a gong with a hammer.

• By using a battery to create sound waves.

What happens to the iron strip in an electric bell when the circuit is broken?

• It moves away from the screw.

• It remains attracted to the electromagnet.

• It gets permanently magnetized.

• It produces a continuous sound.

What causes the hammer in an electric bell to strike the gong repeatedly?

• The battery providing constant power.

• The permanent magnet attracting the hammer.

• The springy metal returning the strip to its initial position.

• The continuous flow of current.

What is the role of the springy metal in the electric bell?

• To produce sound directly.

• To provide power to the electromagnet.

• To maintain contact with the screw.

• To keep the circuit open.

What happens when the bell button is pressed continuously?

• The hammer strikes the gong repeatedly.

• The bell produces a continuous sound.

• The electromagnet stops working.

• The circuit remains open.