question_answer

Two normal uniform magnetic field contain a magnetic needle making an angle 60° with F. Then the ratio of \[\frac{F}{H}\] is                                                                                 [CPMT 1987; DPMT 2001]

A)            1 : 2                                          

B)            2 : 1

C)            \[\sqrt{3}:1\]                       

D)            \[1:\sqrt{3}\]

Correct Answer: D

Solution :

           From figure at equilibrium \[\tan 60{}^\circ =\frac{H}{F}\] Þ \[\sqrt{3}=\frac{H}{F}\]Þ \[\frac{F}{H}=\frac{1}{\sqrt{3}}\]