MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Galvanometer

A moving coil...

Question

A moving coil galvanometer has 48 turns and area of coil is $4 \times 10^{- 2} m^{2}$ . If the magnetic field is 0.2T, then to increase the current sensitivity by 25% without changing area (A) and field (B) the number of turns should become :

A

24

No worries! We‘ve got your back. Try BYJU‘S free classes today!

B

36

No worries! We‘ve got your back. Try BYJU‘S free classes today!

C

60

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

D

54

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is C 60
Current sensitivity $S_{1} = \frac{N B A}{C}$
$S_{1} \propto N$
$∴ \frac{S_{1}}{S_{2}} = \frac{N_{1}}{N_{2}} \Rightarrow \frac{100}{125} = \frac{48}{N_{2}}$
$N_{2} = 60$

Suggest Corrections

thumbs-up

0

Similar questions

Q. A moving-coil galvanometer has its coil of

24

12 Ω

resistance. By how much the number of turns should be increased so that the current sensitivity of the galvanometer increases by

25

%? If, in doing so, the resistance of the coil increases to

20 Ω

, what will be the effect on the voltage-sensitivity of the galvanometer?

Q. A moving coil galvanometer has a coil of effective area

A

and number of turns

N

. The magnetic field

B

is radial. If a current

I

is passed through the coil, the torque acting on the coil is.

Q. A coil of moving coil galvanometer twists through

90^{o}

when a current of one microampere is passed through it.If the area of the coil is

10^{- 4} m^{2}

and it has 100 turns, calculate the magnetic field of the magnet of the galvanometer.Given

k = 10^{- 8} N - m / d e g r e e

Q. A galvanometer coil has

500

turns, and each turn has an average area of

3 \times 10^{- 4} m^{2}

. If a torque of

1.5 Nm

is required to keep this coil parallel to a magnetic field when a current of

0.5 A

is flowing through it, the strength of the field \

(in T)

Q. A rectangular coil of a moving coil galvanometer contains

100

turns, each having area

15 c m^{2}

. It is suspended in the radial magnetic field

0.03

T. The twist constant of suspension fibre is

15 \times 10^{- 10}

/

degree. Calculate the sensitivity of the moving coil galvanometer.

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Electrical Instruments

PHYSICS

Watch in App

explore_more_icon

Explore more

Standard XII Physics

Join BYJU'S Learning Program

CrossIcon