7 Find the paragraphs in the text wich deal with the following subjets

Paragraph1 - Conductors

Paragraph2 - Dangers

Paragraph 3 and 4 - Safety devices

Read the text again, the answer the questions

What would happen if there were a short-circuit in an electrical circuit without a safety device?
A big amount of current flows through the circuit and can cause a fire because the extra energy takes the form of heat.

Which device in the ciruit would react first to a fault current of 40 mA - a circuit breaker or and RCD?

A circuit breaker would react first.

Bob's bathroom circuit has a circuit breaker but i doesn't have an RCD. If Bob got an electric shock while he was in the shower, what would happen? What wouldn't happen? 

Bob dies because of the electric shock and the circuit breaker

1. Electricity moves like the water in a river, it is an uncontrolled amount (a surge).
2. A material which lets electricity through easily is a good conductor.
3. A resistance in the circuit reduces the current.
4. A sudden increase in electricity is a short-circuit.
5. The insulation around the wires in a cable is normally a form of plastic.
6. When a solid turns into a liquid it can cause a fire.
7. RCDs and circuit breakers are safety devices.
8. RCDs protect people and equipment from harm.