A magnet is suspended so as to swing horizontally makes `50` vibrations//min at a place where dip is `30^(0)`, and `40` vibration//min where dip is `45^(0)`. Compare the earth's total fields at the two places.

Explanation

`nalphasqrt(B_(H))`
`rArr(n_(1))/(n_(2))=sqrt((B_(1)Costheta_(1))/(B_(2)Costheta_(2)) ie(50)/(40)=sqrt((B_(1)/(B_(2))xx(Cos30^(@))/Cos45^(@)))`
`rArr(25)/(16)=(B_(1))/(B_(2))xx(sqrt3)/(sqrt2) (or) (B_(1))/(B_(2))=(25)/(8sqrt6)`