Download App

STD 12 - 4. Moving charges and magnetism — NEET STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceNEETSTD 12 - 4. Moving charges and magnetism4 Marks
MCQ
The current sensitivity of a moving coil galvanometer increases by $20 \%$ when its resistance is doubled. Calculate, by what factor does the voltage sensitivity change?
  • ✓
    Becomes $\frac{3}{5}$ times
  • B
    Becomes $\frac{2}{5}$ times
  • C
    No change
  • D
    Decreases by a factor of $\frac{7}{5}$
✓

Answer

Correct option: A.
Becomes $\frac{3}{5}$ times
a
(a)

$S_{i_1}=\frac{N i A B}{k i}=\frac{N A B}{k}$

$S_{i_2}=\frac{1.2 N A B}{k}$

$S_{v_1}=\frac{N A B}{k R}=\frac{S_{i_1}}{R}$

$S_{v_2}=\frac{S_{i_2}}{2 R}=\frac{1.2(N A B)}{k(2 R)}$

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

NEET STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

In a fission process, nucleus $A$ divides into two nuclei $B$ and $C,$ their binding energies being ${E_a},\;{E_b}$ and ${E_c}$ respectively. Then
→
If rotational velocity of a dynamo armature is doubled, then induced $e.m.f$. will become
→
Two capacitors $A$ and $B$ are connected in series with a battery as shown in the figure. When the switch $S$ is closed and the two capacitors get charged fully, then
→
A light bulb of resistance $R=16 \,\Omega$ is attached in series with an infinite resistor network with identical resistances $r$ as shown below. A $10 \,V$ battery drives current in the circuit. ............. $\Omega$ the value of $r$ such that the bulb dissipates about $1 \,W$ of power.
→
Two charges $ + 3.2 \times {10^{ - 19}}\,C$ and $ - 3.2 \times {10^{ - 19}}\,C$ kept $2.4\, \mathop A\limits^o $ apart forms a dipole. If it is kept in uniform electric field of intensity $4 \times {10^5}\,volt/m$ then what will be its electrical energy in equilibrium
→
A ring of radius $R$, made of an insulating material carries a charge $Q$ uniformly distributed on it. If the ring rotates about the axis passing through its centre and normal to plane of the ring with constant angular speed $\omega $, then the magnitude of the magnetic moment of the ring is
→
Which is constant for a satellite in orbit
→
The temperature of $5$ moles of a gas which was held at constant volume was changed from ${100^o}C$ to ${120^o}C$. The change in internal energy was found to be $80$ Joules. The total heat capacity of the gas at constant volume will be equal to ...... $J/K$
→
A smooth tube of certain mass closed at both ends is rotated in a gravity free space and released. The two balls shown in figure moves towards the ends of the tube and stay there. Then which statement is incorrect about this whole system
→
A pendulum is suspended by a string of length $250\,cm$. The mass of the bob of the pendulum is $200\,g$. The bob is pulled aside until the string is at $60^{\circ}$ with vertical as shown in the figure. After releasing the bob. the maximum velocity attained by the bob will be________ $ms ^{-1}$. (if $g=10\,m / s ^{2}$ )
→