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प्रश्न
A compass needle, free to turn in a vertical plane orients itself with its axis vertical at a certain place on the earth. Find out the values of (i) horizontal component of earth's magnetic field and (ii) angle of dip at the place.
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उत्तर
i) As, Horizontal component of earth’s magnetic field, BH = B cosδ
Putting δ = 900
∴ BH = 0
(ii) For a compass needle align vertical at a certain place, angle of dip,
δ = 900.
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