In a deflection magnetometer experiment the deflections produced separately by two short bar magnets kep at the same distance are `45^(@) and 30^(@)`. Then, the ratio of the magnetic moments of the two magnets is

Options

A. `sqrt3:2`
B. `sqrt3:1`
C. `sqrt2:1`
D. `1:sqrt3`

Answer

B

Explanation

The magnetic field in deflection magneto meter
`B"tan"=(mu_(0))/(4pi)(2M)/(d^(3))`
`(M_(1))/(M_(2))=("tan"theta_(1))/("tan"theta_(2))`
Given `theta_(1)=45,theta_(2)=30^(@)`
`(M_(1))/(M_(2))=("tan"45^(@))/("tan"30^(@))=(1)/(1sqrt3)`
`M_(1):M_(2)=sqrt3:1`