2: Electricity Flashcards
Alternating Potential Difference:
A continually oscillating current flow, which results in the potential difference across two points continually oscillating between a positive and negative value.
Amperes (Amps):
The unit of current.
Attraction: A force pulling two opposite charges together, when they are brought near each
other.
Coulomb:
The unit of charge.
Diode:
A component that only allows current to flow through in the forward direction. They have very large resistances in the reverse direction.
Direct Potential Difference:
A one-directional current flow.
Earth Wire:
The green and yellow striped safety wire that prevents an appliance from becoming live.
Electric Field Lines:
Lines representing an electric field, that point in the direction in which a positive charge would experience an electric force.
Electric Field:
A region in which a charge will experience a non-contact, electric force. All
charged objects have an electric field around them, and this field is stronger the closer you are to the charge.
Electrical Current:
The rate of flow of electrical charge. Its value is the same at any position in a single closed loop.
Electrical Work:
When charge flows in a circuit, electrical work is said to be done.
Filament Lamp:
A light emitting component consisting of an enclosed metal filament. Its resistance
increases as the filament’s temperature increases.
Insulation:
The coating around power cables that prevents electrocution and is colour
coded to allow for easy identification.
Light Dependent Resistor (LDR):
A light sensitive component whose resistance increases
as its temperature decreases.
Live Wire:
The brown coloured wire that carries the alternating current from the supply in a
mains power supply.
Mains Electricity:
An a.c supply, which in the UK has a frequency of 50Hz a value of 230V.