हिंदी

A Rectangular Coil of a Moving Coil Galvanometer Contains 100 Turns, Each Having Area 15 cm^2. It is Suspended in the Radial Magnetic Field 0.03 T.

Advertisements
Advertisements

प्रश्न

A rectangular coil of a moving coil galvanometer contains 100 turns, each having area
15 cm2. It is suspended in the radial magnetic field 0.03 T. The twist constant of suspension
fibre is 15 x 10-10 N-m/degree. Calculate the sensitivity of the moving coil galvanometer.

Advertisements

उत्तर

Given: `N = 100, A = 15 cm^2 = 15 xx 10^-4 m^2`,

`B = 0.03 (Wb)/m^2`,

`C = 15 xx 10^-10 "Nm"/"degree"`

To find: Sensitivity (Si)

Formulae: `S_i=(NAB)/c`

`S_i=(100xx15xx10^-4xx0.03)/(15xx10^-10)`

`S_i=3xx10^6 "div"/A`

The sensitivity of a moving coil galvanometer is `3 xx 10^6 "div"/A`.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
2016-2017 (March)

APPEARS IN

वीडियो ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्न

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


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


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?


A galvanometer of resistance G is converted into a voltmeter to measure upto V volts by connecting a resistance R1 in series with the coil. If a resistance R2 is connected in series with it, then it can measures upto V/2 volts. Find the resistance, in terms of R1 and R2, required to be connected to convert it into a voltmeter that can read upto 2 V. Also find the resistance G of the galvanometer in terms of R1 and R2


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


  1. A circular coil of 30 turns and radius 8.0 cm carrying a current of 6.0 A is suspended vertically in a uniform horizontal magnetic field of magnitude 1.0 T. The field lines make an angle of 60° with the normal of the coil. Calculate the magnitude of the counter torque that must be applied to prevent the coil from turning.
  2. Would your answer change, if the circular coil in (a) were replaced by a planar coil of some irregular shape that encloses the same area? (All other particulars are also unaltered.)

Can a galvanometer as such be used for measuring the current? Explain.


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


Define current sensitivity of a galvanometer.


Why does a galvanometer when connected in series with a capacitor show a momentary deflection, when it is being charged or discharged?

How does this observation lead to modifying the Ampere's circuital law?

Hence write the generalised expression of Ampere's law.


Define the current sensitivity of a galvanometer ?


Figure shows two circuits each having a galvanometer and a battery of 3V.

When the galvanometers in each arrangement do not show any deflection, obtain the ratio R1/R2.


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


Outline the necessary steps to convert a galvanometer of resistance RG into an ammeter of a given range ?


What are the advantages of using soft iron as a core, instead of steel, in the coils of galvanometers?


A coil of radius 10 cm and resistance 40 Ω has 1000 turns. It is placed with its plane vertical and its axis parallel to the magnetic meridian. The coil is connected to a galvanometer and is rotated about the vertical diameter through an angle of 180°. Find the charge which flows through the galvanometer if the horizontal component of the earth's magnetic field is BH = 3.0 × 10−5 T.


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


Define the term ‘current sensitivity’ of a moving coil galvanometer.


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


The current sensitivity of a galvanometer is defined as ______.


In a moving coil galvanometer the deflection (Φ) on the scale by a pointer attached to the spring is ______.


The conversion of a moving coil galvanometer into a voltmeter is done by ______.


The coil of a moving coil galvanometer is wound over a metal frame in order to ______.


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 having a coil resistance of 60 Ω shows full-scale deflection when a current of 1.0 amp passes through it. It can be converted into an ammeter to read currents up to 5.0 amp by:


In an ammeter 0.5% of main current passes through galvanometer; If resistance of galvanometer is G, the resistance of ammeter will be.


A multirange voltmeter can be constructed by using a galvanometer circuit as shown in figure. We want to construct a voltmeter that can measure 2V, 20V and 200V using a galvanometer of resistance 10Ω and that produces maximum deflection for current of 1 mA. Find R1, R2 and R3 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:


When a galvanometer is shunted with a 4 Ω resistance, the deflection is reduced to one-fifth. If the galvanometer is further shunted with a 2 Ω wire. The further reduction (find the ratio of decrease in current to the previous current) in the deflection will be (the main current remains the same)


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 having a resistance of 20 Ω and 30 Ω division on both sides has figure of merit 0.005 ampere/division. The resistance that should be connected in series such that it can be used as a voltmeter upto 15 volt, is ______.


A moving coil galvanometer has 150 equal divisions. Its current sensitivity is 10-divisions per milliampere and voltage sensitivity is 2 divisions per millivolt. In order that each division reads 1 volt, the resistance in ohms needed to be connected in series with the coil will be ______.


How is current sensitivity increased?


A resistance of 3Ω is connected in parallel to a galvanometer of resistance 297Ω. Find the fraction of current passing through the galvanometer.


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


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


Current sensitivity of a galvanometer is defined as the:


The figure of merit of a galvanometer is:


The unit in which the current sensitivity of a galvanometer is expressed is:


The voltage sensitivity of a moving coil galvanometer, where G is the resistance of the galvanometer coil, is given by:


The unit of voltage sensitivity 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:


At equilibrium, the deflecting and restoring torques acting on the coil of a moving coil galvanometer satisfy the condition:


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


An ammeter, ideally, has:


A circuit consists of a 3 V source and a 3 Ω resistor. With an ideal ammeter of zero resistance inserted, the current in the circuit is:


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×