Electrical Circuits Flashcards
What is an electric current
An electric current is s flow of electric charge
What do cells and batteries supply
Cells and batteries supply direct current (DC)
What is Direct current (D.C)
Current that always passes in the same direction
What is alternating current (A.C)
Current that is constantly changing direction
What type of supply is mains electricity
Alternating current (A.C) In the UK it has a frequency of 50 cycles per second (50Hz) and is about 230V
What can a diode be used for
A diode may be used for half wave rectification of a.c
Most electrical appliances are connected to the mains using………
A cable and a three pin plug
What are the colours of the different wires
Neutral wire = bLue (goes Left)
Live wire= bRown (goes Right)
Earth wire = green and yellow sTripes (goes to the Top
What is the case made of and why
The case is made of tough plastic or rubber, because these materials are good electrical insulators
What are the three pins made from and why
The three puns are made from brass, which is a good conductor of electricity
What happens if an electrical fault causes too great a current to flow
If an electrical fault causes to great a current to flow, the circuit is disconnected by a fuse or a circuit breaker in the live wire
What happens when the current in a fuse wire exceeds the rating of the fuse
It will melt, breaking the circuit
The thicker the wire in the fuse, …………
The higher the fuse’s rating .
This us because the thinner wire cannot take such a big load as the thicker one can; the thinner one will just melt at the same voltage and current that the thicker one would be able to take
What are some circuits protected by
Residual current circuit breakers (RCCBs)
Which is faster, a fuse or RCCBs
RCCBs operate much faster than a fuse
