Question

magnetic needle free to rotate in a vertical plane, orients itself vertically at a certain place on earth. what is the value of horizontal component of earths magnetic field at this place ?

Answer 1

$\huge\red{Answer}$

At the two magnetic poles, the magnetic needle rests vertically.

Hence, at poles, δ = 90°

As, Horizontal component, H=

cos δ = 0°

And at a place on the magnetic poles, earth's magnetic field is perpendicular to the surface of earth, i.e., vertical.

Therefore, angle of dip (δ) = 90°

The angle that a magnetic needle makes with the horizontal plane at any specific location is dip angle.

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