Physics-
General
Easy
Question
An aluminium ring B faces an electromagnet A. The current I through A can be altered
- Whether I increases or decreases, B will not experience any force
- If I decrease, A will repel B
- If I increases, A will attract B
- If I increases, A will repel B
The correct answer is: If I increases, A will repel B
If current through A increases, crosses (X) linked with coil B increases, hence anticlockwise current induces in coil B. As shown in figure both the current produces repulsive effect.
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