Short answerEasy1 mark
9(iii)(b)
Given below is a circuit to study the magnetic effect of electric current. ABCD is a cardboard kept perpendicular to the conductor XY. A magnetic compass is placed at the point P of the cardboard. P1 and P2 are the positions of the magnetic compass, before and after passing a current through XY respectively.
If resistance R is increased, then what will be the effect on the magnetic lines of force around the conductor?
Topic: Effect of current on magnetic field strength
Question wording verified against source paper
Answer
Exam answer
The magnetic field becomes weaker and the magnetic lines become less dense.
Explanation
Increasing R reduces the current; magnetic field strength around the conductor is proportional to current.
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