Short answerEasy1 mark
9(iii)
A copper rod PQ carrying current is kept in a magnetic field as shown in the diagram.
What will be the effect on the force experienced, if the rod PQ is replaced by another copper rod of same length but of greater cross-sectional area?
Topic: Effect of current on magnetic force
Question wording verified against source paper
Answer
Exam answer
The force increases.
Explanation
A larger cross-sectional area lowers resistance, increasing current for the same supply voltage.
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