Physics Unit 2 Electricity Chp 1 Main Electricity

Explain 3 types of wires with their functions and colours in a ring main circuit.

Earth wire (Green, yellow): No current. Protects the person or device when a fault occurs. 

Neutral wire (Blue): Completes the circuit

Live wire (Brown): Carries electrical energy through this wire to the appliance

Part of OBJQ

Explain a fuse in terms of its shape, constituents, common domestic appliance and correct advice while installing.

Shape: Cylinder shape

Constituent: Thin piece of wire made of metal to conduct electricity 

Common domestic appliance: 3A, 5A, 13A

Advice: The fuse’s maximum value must be a little larger than the appliance’s.

Part of OBJQ

FAQ

Explain how a fuse protects the wire in the circuit box from overheating

When current flows above the maximum value of the fuse, the fuse’s wire becomes hot and melts, causing the fuse to break the circuit.

Part of OBJQ

FAQ

State the 2 advantages of circuit breakers.

-More sensitive

-Resettable