Electricity (definitions) Flashcards
Coulomb
The charge transported by a steady current of one ampere in one second.
Electric Current
The flow of charged particles.
Conventional Current
Direction in which positive charges would flow In a circuit.
Resistance
Potential difference/Current
Resistivity
Resistivity = RA/L, where R is the resistance of the material, A is the cross-sectional area of the material and L is the length of the material.
Ohm’s Law
For a metallic conductor at constant temperature, the Current in the conductor is directly proportional to the potential difference across it’s ends.
Kirchhoff’s First Law
The sum of the currents entering a point is equal to the sum of current leaving the same point.
Kirchhoff’s Second Law
The sum of the e.m.f’s around any closed loop in a circuit is equal to the sum of the p.d’s around the same closed loop.
Mean Drift Velocity
The average distance travelled by the electrons along the wire per second.
Kilowatt-hour
The energy transformed by a 1kW devise in a time of 1 hour.
J -> kWh = divided by 3,600,000
kWh -> J = multiplied by 3,600,000
Potential Difference (p.d)
The energy transferred (lost) per unit charge.
Electromotive Force (e.m.f)
The energy transferred (gained) per unit charge.
