Physicshard · Past Paper
Which of the following will not change the direction of rotation of a DC motor?
AReversing battery terminals
BReversing magnetic field poles
CReversing both battery and magnetic poles
DChanging the commutator type
✓ Correct Answer: C — Reversing both battery and magnetic poles
Reversing both current and magnetic field cancels out the change in force direction (Left-hand rule).
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