A certain amount of current when flowing in a properly set tangen… - Vidyadip

MCQ

A certain amount of current when flowing in a properly set tangent galvanometer, produces a deflection of $45^{\circ}$. If the current be reduced by a factor of $\sqrt{3}$, the deflection would

A
Decrease by $30^{\circ}$
✓
Decrease by $15^{\circ}$
C
Increase by $15^{\circ}$
D
Increase by $30^{\circ}$

✓

Answer

Correct option: B.

Decrease by $15^{\circ}$

In tangent galvanometer, $I \propto \tan \theta$
$ \therefore \frac{I_1}{I_2}=\frac{\tan \theta_1}{\tan \theta_2} \Rightarrow \frac{I_1}{I_1 / \sqrt{3}}=\frac{\tan 45^{\circ}}{\tan \theta_2} $
$ \Rightarrow \sqrt{3} \tan \theta_2=1 \Rightarrow \tan \theta_2=\frac{1}{\sqrt{3}} \Rightarrow \theta_2=30^{\circ}$
So deflection will decrease by $45^{-}-30=15$,

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

Explore more

More "MCQ" from Magnetism→Magnetism — all question types→JEE physics STD 12 Science question papers→CBSE Board STD 12 Science question papers→CBSE Board question paper generator→

Similar questions

A wave travels in a medium according to the equation of displacement given by $y(x, t)=0.03 \sin \pi(2 t-0.01 x)$
where $y$ and $x$ are in metres and $t$ in seconds. The wavelength of the wave is

An achromatic combination of lenses is formed by joining

When the displacement is half the amplitude, the ratio of potential energy to the total energy is

A particle of mass $m_1$ is moving with a velocity $v_1$ and another particle of mass $m_2$ is moving with a velocity $v_2$. Both of them have the same momentum but their different kinetic energies are $E_1$ and $E_2$ respectively. If $m_1>m_2$ then

$E_1 < E_2$
$\frac{E_1}{E_2}=\frac{m_1}{m_2}$
$E_1>E_2$
$E_1=E_2$

A train is moving with velocity $20\ m / sec$. on this dust is falling at the rate of $50\ kg /$ minute. The extra force required to move this train with constant velocity will be

Bohr's atom model assumes

Two rods having thermal conductivity in the ratio of $5: 3$ having equal lengths and equal cross-sectional area are joined by face to face. If the temperature of the free end of the first rod is $100 C$ and free end of the second rod is $20 C$. Then temperature of the junction is

Dimensions of luminous flux are

A point object is placed at the center of a glass sphere of radius $6\ \mathrm{cm}$ and refractive index $1.5.$ The distance of the virtual image from the surface of the sphere is

In the following figure, four curves $A, B, C$ and $D$ are shown. The curves are