Understanding Static Electricity and Electric Circuits

The video tutorial explores static electricity, demonstrating how rubbing a polythene strip with a duster creates static charge. It explains the behavior of charges in everyday scenarios, such as shoes on carpet and helicopters in flight. The tutorial covers the concepts of conductors and insulators, electric current, and potential difference. It also delves into the role of voltage and current in lighting systems, using Blackpool's illuminations as an example. Finally, it discusses resistance and conductivity, highlighting the use of resistivity meters to identify materials underground.

What happens when you rub a polythene strip with a cloth?

• The strip becomes neutral.

• Negative charges are transferred to the strip.

• The strip loses all its charges.

• The strip becomes positively charged.

Why does static electricity build up when walking on a carpet?

• The carpet transfers positive charges to the shoes.

• The carpet is a conductor.

• Negative charges move from the carpet to the shoes.

• The shoes lose all their charges.

How can static electricity be safely discharged from a helicopter?

• By using rubber tires.

• By flying at a lower altitude.

• By attaching a static line to the ground.

• By using a plastic rope.

What is the role of conductors in an electric circuit?

• They store electrical energy.

• They allow charges to flow freely.

• They increase the resistance.

• They prevent the flow of charges.

What is needed to get charges moving in a circuit?

• An insulator.

• A potential difference.

• A high resistance.

• A complete circuit.

How does increasing the voltage affect the brightness of a light bulb?

• It makes the bulb dimmer.

• It has no effect on the bulb.

• It turns the bulb off.

• It makes the bulb brighter.

What does a resistivity meter measure?

• The voltage of a circuit.

• The current flowing through a wire.

• The electrical resistance of materials.

• The potential difference across a bulb.

Which material is likely to have a low electrical resistance?

• Glass

• Metal

• Plastic

• Wood

What happens to the current in a circuit when resistance is high?

• The current increases.

• The current decreases.

• The current remains the same.

• The current stops completely.

Why are metals used for wires in electrical circuits?

• They have high resistance.

• They are good insulators.

• They are lightweight.

• They have low resistance.