physics knowldege questions Flashcards
What does DC stand for?
direct current
What does AC stand for?
alternating current
Is UK mains electricity AC or DC?
alternating current
What Potential difference is UK mains electricity?
230 V
What frequency is UK mains electricity?
50 Hz
What is the name for the device which increases the potential difference in the national grid?
step up transformer
What is the name for the device which lowers the potential difference in the national grid?
step down transformer
What is the name for the whole system (cables, step up transformers and step down transformers) that ensure electricity gets around the country?
the national grid
What is the name for the brown wire in a mains plug, which has the high Potential difference?
live wire
What is the name for the blue wire in a mains plug, which completes the circuit?
neutral wire
What is the name for the green and yellow wire in a mains plug that is used for safety?
earth wire
What is the unit of potential difference?
Volt (V)
What is the unit of current?
Amps (A)
What is the unit of resistance?
Ohm (Ω)
What is the unit of charge?
Coulomb (C)
What is the unit of power?
Watt (W)
What is the unit of time?
second (s)
What is the unit of energy and work done?
Joule (J)
Write the equation which links power, time and energy
energy= power x time
Write the equation which links current resistance and power
Power = current2 x resistance
Write the equation which links current, power and potential difference
Power = current x potential difference
