Physics
A magnetic compass is present on a small table, very close to the wall in a room. A man enters the room and switches on the Air Conditioner fitted near the ceiling. He observes that the needle in the compass shows immediate deflection. Identify the most probable reason for the deflection.
- Air blowing in the room.
- Current starts flowing through AC wire concealed in the adjacent wall.
- Vibrations are produced when the Man starts talking to his wife in the kitchen.
- Vibrations were produced due to a file in his hand that fell on the ground.
Electro-Magnetism
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Answer
Current starts flowing through AC wire concealed in the adjacent wall.
Reason — When the AC is switched on, electric current flows through the concealed wires, generating a magnetic field around them. This magnetic field interacts with the magnetic compass, causing the needle to deflect. Air movement or vibrations don’t affect magnetic fields, so they wouldn’t cause the needle to move.
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