Electricity Flashcards
State Coulomb’s Law.
The electrostatic force between two point charges is directly proportional to the product of their charges and inversely proportional to the square of their separation.
What is electric field strength?
It is the electric force acting per unit positive charge placed at that point.
What is electric potential energy?
It is the work done by an external agent in bringing a charged body from infinity to the point.
What is electric potential?
It is work done per unit positive charge by external agent in bringing a charged body from infinity to the point.
Define resistance.
It is ratio of potential difference to current.
Define charge.
It is the product of current and time.
What is electromotive force?
The amount of other forms of energy converted to electrical energy per unit charge in a source.
(It is energy transferred by a source in driving unit charge round a complete circuit)
Define ohm.
It is electric resistance between two points of conductor in a ratio of potential different to current.
R = V/I
Define a volt.
It is potential difference between two points in a circuit where (1) joule of energy is converted to other forms of energy when 1 coulomb of charge passes through a device.
What is potential difference?
It is the amount of electrical energy converted to other forms of energy per unit charge in a device.
Define current.
It is the rate of flow of charged particles.
Define resistivity.
It is the relationship between the resistance of a material to its length and cross-sectional area at a constant temperature. Higher resistivity resists the flow of current more.
