A tangent galvanometer carrying a certain current gave a defelction of `30^(@)`. If the galvanometer is taken to another location where the earth's horizontal component of magnetic induction is one thrid of the previous value, The deflection for the same current will be

Options

A. `60^(@)`
B. `45^(@)`
C. `90^(@)`
D. `30^(@)`

Answer

1

Explanation

If K is the reduction factor of the galvanometer, then `K=(2rB_(H)r)/(mu_(0)n).` As `B_(H)` is reduced to `1//3^(rd),K` becomes `K//3`. Use `i=Ktan theta`