Same chapter2 marksDifficulty: Medium
Why does a transformer not work on a direct-current supply?
Electromagnetism
3 marksDifficulty: Medium
State the principle of an electric motor and name the rule used to find the direction of rotation.
Original Khojo Papers practice question — not from a past board paper.
Answer
A current-carrying coil placed in a magnetic field experiences a couple that makes it rotate. The direction of the force on each side of the coil is found by Fleming's left-hand rule.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
A split-ring commutator reverses the current in the coil every half turn so that the rotation continues in the same sense.
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