Electric Current and Circuit Safety

The video discusses how electric current heats objects, which is beneficial for appliances like heaters and bulbs but can be dangerous if excessive. It introduces electric fuses as a safety device to prevent overheating by breaking the circuit when current is too high. The video also covers the limitations of traditional fuses and introduces Miniature Circuit Breakers (MCBs) as a modern alternative that automatically resets.

Which of the following is an advantage of electric current heating up objects?

• It limits the amount of electric current.

• It prevents overheating of devices.

• It helps in the functioning of electric water heaters.

• It can cause appliances to catch fire.

What is a potential drawback of electric current heating up objects?

• It can make devices more efficient.

• It makes devices more durable.

• It reduces the electric current flow.

• It can cause devices to overheat and catch fire.

What is the primary function of an electric fuse?

• To make devices more efficient.

• To reduce the electric current flow.

• To prevent devices from overheating by breaking the circuit.

• To increase the electric current.

Which materials are commonly used to make fuse wires?

• Plastic and rubber

• Zinc, copper, silver, or aluminium

• Iron and steel

• Gold and platinum

Why is the rest of the fuse switch made of non-combustible material?

• To make it more attractive

• To ensure it does not catch fire

• To increase its weight

• To make it more expensive

What happens when there is a heavy current in the circuit with a fuse?

• The fuse wire strengthens and continues the circuit.

• The fuse wire cools down.

• The fuse wire melts and breaks the circuit.

• The fuse wire changes color.

What is a disadvantage of traditional electric fuses?

• They increase the electric current.

• They cannot reform themselves once melted.

• They are too expensive.

• They are too large.

What is another name for Miniature Circuit Breakers (MCBs)?

• Current limiters

• Electric switches

• Automatic fuses

• Voltage regulators

How do MCBs function when there is excess current flow?

• They increase the current flow.

• They automatically switch off.

• They change the circuit path.

• They melt like traditional fuses.

What is an advantage of MCBs over traditional fuses?

• They require manual replacement.

• They automatically switch on when the current flow is normal.

• They are cheaper.

• They are larger in size.