MCQ
Two tangent galvanometer coils of same radius connected in series. The current flowing produces deflection of $60^o$ and $45^o$. The ratio of number of turns in coil is
  • A
    $\frac {4}{3}$
  • B
    $\frac {\sqrt 3+1}{1}$
  • C
    $\frac {\sqrt 3+1}{\sqrt 3-1}$
  • $\frac {\sqrt 3}{1}$

Answer

Correct option: D.
$\frac {\sqrt 3}{1}$
d
Tangent galvanometers are connected in series so current will be same in both.

${\mathrm{k}_{1} \tan \theta_{1}=\mathrm{K}_{2} \tan \theta_{2}}$

${\frac{\mathrm{k}_{1}}{\mathrm{k}_{2}}=\frac{\tan \theta_{2}}{\tan \theta_{1}}=\frac{1}{\sqrt{3}}}$

$\mathrm{k} \propto \frac{\mathrm{R}}{\mathrm{N}}$ (radius is same for both)

$\frac{\mathrm{K}_{1}}{\mathrm{K}_{2}}=\frac{\mathrm{N}_{2}}{\mathrm{N}_{1}}$

$\Rightarrow \frac{\mathrm{N}_{1}}{\mathrm{N}_{2}}=\frac{\mathrm{K}_{2}}{\mathrm{K}_{1}}=\frac{\sqrt{3}}{1}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free