P2 - electrical circuits
by A Jenkins
1. measurements
1.1. voltage
1.1.1. voltmeter
1.1.1.1. parallel
1.1.2. volts (V)
1.2. current
1.2.1. flow of charge
1.2.2. ammeter
1.2.2.1. series
1.2.3. amps (A)
1.3. power
1.3.1. energy used per second
1.3.2. Watts (W)
2. component graphs
2.1. resistor
2.1.1. straight line
2.2. bulb
2.2.1. curve
2.3. diode
2.3.1. current only flows when voltage is grater than 0.6V
3. plug
3.1. live
3.1.1. fuse
3.1.2. brown
3.2. earth
3.2.1. green and yellow
3.3. neutral
3.3.1. blue
3.4. insulation
4. safety
4.1. earth lead
4.1.1. current flows straight to earth
4.1.2. protects against electric shock
4.2. fuse
4.2.1. melts if current is too big
4.2.2. no protection against electric shock
4.3. miniature circuit breaker (mcb)
4.3.1. replace fuses
4.3.2. electromagnet
4.3.3. breaks circuit if current is too big
4.3.4. no protection against electric shock
4.4. residual current device (rcd)
4.4.1. protects against electric shocks
4.4.2. compares current in live and neutral wires
4.4.3. should be used in gardens