electric circuits

Created by

aize

Cards (25)

A cell is a store of chemical energy
A battery is two of more cells
A switch completes/breaks the circuit
A light bulb converts electrical energy to light and heat
A fixed resistor has a known resistance
A variable resistor has an adjustable resistance
A thermistor is a resistor that changes resistance depending on temperature
A LDR is a resistor that changes resistance depending on the light intensity
A fuse is a safety device that melts when a large current flows
A voltmeter measures potential difference and is always connected in parallel
An ammeter measures current and is always connected in series
A diode controls the direction of current in a circuit
An LED is a energy efficient light bulb
A motor converts electrical energy to kinetic energy
A series circuit is a circuit in which the current flows in one path
A parallel circuit is a circuit that has two or more paths for the current to flow through
Current measured in Amps is the rate of flow of charge in a circuit, charge is measured in Coulombs and time is measured in seconds. One amp = one Coulomb per second
Current = charge / time
The equation for current in symbols is
$I =$ $\Delta Q / \Delta t$
Ohms law: Resistance = Voltage / Current
The equation for Ohms law in symbols is R = V / I
An electrical wire contains, three wires. These wires are made of copper because it is a good conductor of electricity. Each wire is made of thin strands of copper to keep the cable flexible. Each wire is encased in plastic to stop the wires touching and causing a short circuit. Plastic is used as it is a good insulator, as well as being tough and flexible. The whole cable is encased in another layer of plastic.
The earth wire is green and yellow, the neutral wire is blue and the live wire is brown
When choosing the fuse for a device you should always choose one with the ampage above the operating current of the device
Earth wires are always used if an appliance has a metal case. If there is a fault in the appliance causing the live wire to touch the case, the current surges down the earth wire and the fuse melts