At a place, the horizontal component of earth's magnetic field is B and angle of dip is `60^@`. What is the value of horizontal component of the earth's magnetic field at equator?

Explanation

The value of horizontal component of the earth.s magnetic field at equator is equal to the total magnetic field `.B_C.` of earth i.e., `(B_H)` equator =` B_E`
As at a given place, horizontal component `B_H = B_E cos delta`, where `delta ` is the angle of dip. Hence , we have `B= B_E cos 60^@ = 1/2 B_E implies B_E = 2B`
`implies (B_H)_("equator") = B_E = 2B`