Electric circuits

Conventional current flow

Flow from positive to negative used to describe the direction of current in a circuit

Current

The rate of flow of charge in a circuit measured in amperes and was symbol I

Detecting circuit

A circuit with a potential divider with one of the resistors being a

semiconductor which when an external condition changes will change its resistance and

change the voltage across the other resistor in the potential divide

Diode

Components that allow current through in one direction. In the correct direction,

diodes have a threshold voltage (typically 0.6 V) after which current flows normally.

EMF

The energy supplied by a source per unit charge passing

through the source, measured in volt

Elector flow

The flow of electrons in a circuit, from negative to positive.

Internal resistance

The unavoidable resistance any power source will have that makes it

harder for current to flow through the source. It causes energy to be dissipated in the source.

Kirchoff's first law

The total current entering a junction is equal to the total current leaving it

Kirchoff's 2nd law

The sum of EMF in any loop of the circuit is equal to the sum of the

potential differences of each component.

LDR

-When these components are illuminated with light their

resistance goes down. As light intensity increases resistance decreases.

Ohmic conductor

A conductor following Ohm’s law where current flowing through it is

directly proportional to the potential difference between each end of the conductor. This only

holds if the conductor is kept at a constant temperature.

Ohm's law

Electric current is proportional to potential difference and inversely proportional* to resistance

Parallel connection

When two electrical components are on separate loops to one another

in a circuit. Potential difference over each loop is the same, current is split between branches

p.d.

Potential divider

Power

Resistance

Semiconductor

Resistvity

Terminal potential difference

Thermistor

Variable resistor

Voltmeter