मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

Calculate the Sensitivity of the Moving Coil Galvanometer

Advertisements
Advertisements

प्रश्न

A rectangular coil of a moving coil galvanometer contains 50 turns each having area 12 cm2 . It is suspended in radial magnetic field 0.025 Wb/m2 by a fibre of twist constant 15 x10-10 Nm/degree. Calculate the sensitivity of the moving coil galvanometer.

Advertisements

उत्तर

Given:-

N = 50, A = 12 cm2 = 12 x 10-4 m2,

B = 0.025 Wb/m2,

C = 15 x 10-10 Nm/degree

To find:- Sensitivity (Si)

Formula: Si = NAB/C

Calculation: From formula,

`S_i=(50xx12xx10^-4xx0.025)/(15xx10^-10`

`thereforeS_i=10^6"div/A"`

The sensitivity of a moving coil galvanometer is 106 div/A.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
2014-2015 (October)

APPEARS IN

व्हिडिओ ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्‍न

The combined resistance of a galvanometer of resistance 500Ω and its shunt is 21Ω. Calculate the value of shunt.


Show that the current flowing through a moving coil galvanometer is directly proportional to the angle of deflection of coil.


Write the underlying principle of a moving coil galvanometer.


Obtain the expression for current sensitivity of moving coil galvanometer.


A circular coil of 250 turns and diameter 18 cm carries a current of 12A. What is the magnitude of magnetic moment associated with the coil?


Why is it necessary to introduce a cylindrical soft iron core inside the coil of a galvanometer?


Increasing the current sensitivity of a galvanometer may not necessarily increase its voltage sensitivity. Explain, giving reason.


The fraction of the total current passing through the galvanometer is ............ .

a) `S/(S+G)`

b) `G/(S+G)`

c) `(S+G)/G`

d) `(S+G)/S`


How will you convert a moving coil galvanometer into a voltmeter?


With the help of a neat and labelled diagram, explain the principle and working of a moving coil galvanometer ?


Define the current sensitivity of a galvanometer ?


Write current sensitivity of a galvanomete S.I. unit. 


Explain, giving reasons, the basic difference in converting a galvanometer into (i) a voltmeter and (ii) an ammeter?


Draw a labelled diagram of a moving coil galvanometer and explain its working. What is the function of radial magnetic field inside the coil?


Why are the pole pieces of a horseshoe magnet in a moving coil galvanometer made cylinder in shape? 


A moving coil galvanometer has a coil of resistance 59 Ω. It shows a full-scale deflection for a current of 50 mA. How will you convert it to an ammeter having a range of 0 to 3A?


State how a moving coil galvanometer can be converted into an ammeter.


Explain the significance of a radial magnetic field when a current-carrying coil is kept in it. 


A galvanometer coil has a resistance of 15 Ω and the metre shows full scale deflection for a current of 4 mA. How will you convert the metre into an ammeter of range 0 to 6 A?


The AC voltage across a resistance can be measured using a ______.


The deflection in a moving coil galvanometer is ______.


A moving coil galvanometer has N number of turns in a coil of effective area A, it carries a current I. The magnetic field B is radial. The torque acting on the coil is ______.

An electric charge in uniform motion produces ______.

The current sensitivity of a galvanometer increase by 20%. If its resistance also increases by 25%, the voltage sensitivity will ______.


Assertion (A): On Increasing the current sensitivity of a galvanometer by increasing the number of turns may not necessarily increase its voltage sensitivity.

Reason (R): The resistance of the coil of the galvanometer increases on increasing the number of turns.

Select the most appropriate answer from the options given below:


A galvanometer of resistance 100 Ω gives a full-scale deflection for a current of 10−5 A. To convert it into an ammeter capable of measuring up to 1 A we should connect a resistance of ______.


A multirange current meter can be constructed by using a galvanometer circuit as shown in figure. We want a current meter that can measure 10 mA, 100 mA and 1A using a galvanometer of resistance 10 Ω and that prduces maximum deflection for current of 1mA. Find S1, S2 and S3 that have to be used


A voltmeter of variable ranges 3 V, 15 V, 150 V is to be designed by connecting resistances R1, R2, R3 in series with a galvanometer of resistance G = 20 Ω, as shown in Fig. The galvanometer gives full pass through its coil for 1 mA current i.e. "gives full pass through it's coil for 1 mA current". Then, the resistances R1, R2 and R3 (in kilo ohms) should be, respectively:


A galvanometer coil bas 500 turns and each tum has an average area of 3 × 10-4 m2. 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) is ______.


A galvanometer shows full-scale deflection for current Ig. A resistance R1 is required to convert it into a voltmeter of range (0 - V) and a resistance R2 to convert it into a voltmeter of range (0 - 2V). Find the resistance of the galvanometer.


How is current sensitivity increased?


Explain in brief the basic construction of a moving-coil table galvanometer whit a neat labelled diagram.


A voltmeter has a range of 0 - 20 V and a resistance of 500 Q. Explain how can be used to measure voltages from 0 - 200 volt?


A moving coil galvanometer of resistance 55 Ω produces a full scale deflection for a current of 250 mA. How will you convert it into an ammeter with a range of 0 - 3A?


To convert a moving coil galvanometer into an ammeter we need to connect a ______.


Assertion: When an electric current is passed through a moving coil galvanometer, its coil gets deflected.

Reason: A circular coil produces a uniform magnetic field around itself when an electric current is passed through it.


The figure below shows a circuit containing an ammeter A, a galvanometer G and a plug key K. When the key is closed:


A sensitive electromagnetic instrument used to detect and measure small electric currents (of the order of microamperes to milliamperes) by measuring the deflection of a current-carrying coil placed in a uniform magnetic field is called a:


Current sensitivity of a galvanometer is defined as the:


The figure of merit of a galvanometer is:


The figure of merit k of a galvanometer is given by:


When a current-carrying coil of N turns and area A, carrying current I, is placed in a magnetic field B, the magnitude of the magnetic torque acting on it is:


In a suspended-coil galvanometer, the phosphor-bronze strip serves to:


The pointer used to read the deflection on the calibrated scale of a moving coil galvanometer is made of:


The non-magnetic frame of a moving coil galvanometer is made of aluminium, and its function is to provide:


An ammeter, ideally, has:


A voltmeter is connected across a component:


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×