Electricity
Edexcel GCSE Physics revision on Electricity. Aligned to the Pearson Edexcel GCSE Physics 1PH0 specification. This bank has 33 practice questions on this topic.
Sample questions (3 of 33)
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Question 1
The unit of current is the...
- A) Volt
- B) Ampere (amp)
- C) Watt
- D) Ohm
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Answer: Ampere (amp)
Common units: CHARGE in coulombs (C), CURRENT in amperes (A) = C/s, VOLTAGE in volts (V), RESISTANCE in ohms, POWER in watts (W). Typical: phone charger ~1 A, kettle ~12 A, lightning bolt ~10,000 A briefly. Symbol: I for current, V for voltage (potential difference), R for resistance, P for power, Q for charge.
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Question 2
Ohm's law states V = ...
- A) I x R
- B) I + R
- C) I / R
- D) R / I
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Answer: I x R
V = IR. Rearranged: I = V/R, R = V/I. Higher voltage + same resistance = bigger current. Higher resistance + same voltage = smaller current. The relationship holds for OHMIC components (most resistors, wires). NON-OHMIC: bulb filament (resistance rises with temperature), diode (one-way), thermistor (resistance falls with temperature).
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Question 3
A device with 5 amps flowing through it under a potential difference of 30 volts has a resistance of...
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Answer: 6
Rearrange V = IR -> R = V / I. 30 / 5 = 6 ohms. Higher resistance means less current for the same voltage. Typical resistances: copper wire ~0 ohms (almost zero), 60W bulb ~800 ohms, electric heater ~24 ohms (low resistance for high current/power).
Want to test yourself on the remaining cards for this topic?
30 more questions on Electricity — plus mistakes tracking and spaced repetition across the whole Physics spec.