Physics electricity flashcards

The force per unit charge at a point in an electric field

electric field strength

The work done in bringing a charge from one point to another

potential difference

the potential difference is one volt if one joule of work is required to move one coulomb

The volt

The ratio of charge on the body to its potential difference

capacitance

A body has capacitance of one farad if the addition to the body of one coulomb raises the voltage by 1

The Farad

The force between two charges is directly proportional to the product of the charges and inversely proportionate to the square of the distance between them

Coulombs law

The ratio of voltage across to current flowing through

resistance

a conductor has resistance of one ohm if a current of one amp flows when a potential of one volt is applied

The ohm

For a metallic conductor at constant temperature the current will be proportional to the voltage 

Ohms law 

The resistance of an object of that material with unit area and unit length

Resistivity

A material whose resistivity is between that of a conductor and insulator 

semiconductor 

The force experienced by a conductor of length one meter carrying a current of one amp at right angles to the field

Magnetic Flux Density 

the current which, if maintained by two parallel, infinitely long wires of negligible cross section placed one meter apart in vacuum would produce between the wires a force of 2×10^-7 newtons per meter length of the wire  

The amp

When there is a change in the magnetic flux linking a coil, an emf is induced in that coil. 

Faradays law 

The direction of an induced current is such as to oppose the change causing it

Lenz’es law