Question

In a deflection magnetometer experiment, the deflections produced separately by two short bar magnets kept at the same distance are 45${}^0$ and 30${}^0$. Then the ratio of the magnetic moments of the two magnets is :

• A. $\sqrt{3}:2$
• B. $\sqrt{3}:1$
• C. $\sqrt{2}:1$
• D. $1:\sqrt{3}$

Answer 1

The correct option is B $\sqrt{3}:1$

By comparison of magnetic moment,

$\frac{M_1}{M_2}=\frac{\tan {\theta }_1}{\tan {\theta }_2}$

$\Rightarrow \frac{\tan 45°}{\tan 30°}$

$\Rightarrow \frac{1}{1/\sqrt{3}}$

$\Rightarrow \frac{\sqrt{3}}{1}.$

Hence, option : B.