The true value of angle of dip at a place is 60^(@)`, the apparent dip in a inclined at an angle of `30^(@)` with magnetic meridian is

Options

A. `tan^(-1)"(1)/2
B. `tan^(-1)(2)`
C. `tan^(-1)"(2/3)`
D. None of these

Answer

B

Explanation

`tan varphi^(')=(tan varphi)/(cos beta)`, where `varphi^(')`= Apparent angle of dip,
`varphi`= True angle of dip, `beta`= Angle made by vertical plane with magnetic meridian.
`impliestan varphi^(')= (tan 60^(@))/(cos 30^(@))=2implies varphi^(')=tan^(-1)(2)`