Q1. [1] medium thorough-understanding
A charge of 180 C flows through a conductor in 2 minutes. (i) Calculate the electric current through the conductor. (ii) If the potential difference across the conductor is 12 V, find its resistance. State the law you used in part (ii).
Generated by claude-sonnet-4-6 · 2026-06-26 01:09 · grounding rag
Model Answer
(i) I = Q/t = 180 C / (2 × 60) s = 180/120 = 1.5 A
(ii) Using Ohm's Law: R = V/I = 12/1.5 = 8 Ω
Ohm's Law states that the potential difference across a conductor is directly proportional to the current through it at constant temperature (V = IR).
Explanation
- Convert time to seconds: 2 min = 120 s.
- Formula for current: I = Q/t.
- For resistance, apply Ohm's Law: R = V/I.
- Always name the law explicitly — examiners award a separate mark for it.