Question

A dip needle is in the plane of magnetic meridian
shows 30°. Now it is rotated by an angle 30°, then
new dip angle will be​

Answer 1

Explanation:

Let the vertical component of earth's magnetic field be V and its horizontal component at magnetic meridian be H.

Then the angle of dip θ at magnetic meridian will be given by

tanθ=VH......[1]

When the dip needle is suspended at an angle of 30∘ to the earth magnetic meridian then it makes an angle 45∘ with the horizontal.

In this situation vertical component of earth's field responsible for its orientation with the horizontal direction, remains same as V but the component in horizontal direction becomes Hcos30∘

So tan45∘=VHcos30∘

⇒VH=cos30∘.......[2]

Comparing [1] and [2] we get

tanθ=cos30∘=√32

⇒θ=tan−1(√32)≈40.9∘

Answer 2

Answer:

40.9'

Magnetic dip :

The angle made between earth total magentic field and its horizontal component