Q. The tangent galvanometers having coils of the same radius are connected in series. Same current flowing in them produces deflections of $60{^\circ}$ and $45{^\circ}$ respectively. The ratio of the number of turns in the coil is
A) $\frac{4}{\sqrt{3}}$
B) $\frac{\sqrt{3} + 1}{1}$
C) $\frac{\sqrt{3} + 1}{\sqrt{3} - 1}$
D) $\frac{\sqrt{3}}{1}$
Explanation
(d) For tangent galvanometer the number of turns
$N \propto \tan\theta$
Hence, $\frac{N_{1}}{N_{2}} = \frac{tan\ \theta_{1}}{tan\ \theta_{2}}$
Or $\frac{N_{1}}{N_{2}} = \frac{tan\ 60{^\circ}}{tan\ 45{^\circ}}$
Or $\ \frac{N_{1}}{N_{2}} = \frac{\sqrt{3}}{1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.