Advertisements
Advertisements
Question
To convert a moving coil galvanometer into an ammeter we need to connect a ______.
Options
small resistance in parallel with it
large resistance in series with it
small resistance in series with it
large resistance in parallel with it
Advertisements
Solution
To convert a moving coil galvanometer into an ammeter we need to connect a small resistance in parallel with it.
Explanation:
To turn a moving coil galvanometer into an ammeter, a low-resistance, known as a shunt, is connected parallel to the galvanometer. The shunt allows the majority of the current to bypass the galvanometer, allowing it to measure high currents without being harmed. This ensures that the galvanometer deflection is proportional to the total current in the circuit.
APPEARS IN
RELATED QUESTIONS
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.
Show that the current flowing through a moving coil galvanometer is directly proportional to the angle of deflection of coil.
Why does a galvanometer show a momentary deflection at the time of charging or discharging a capacitor? Write the necessary expression to explain this observation.
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?
An ideal voltmeter has _______.
(A) low resistance
(b) high resistance
(C) infinite resistance
(D) zero resistance
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
Draw a labelled diagram of a moving coil galvanometer. Describe briefly its principle and working.
Why is it necessary to introduce a cylindrical soft iron core inside the coil of a galvanometer?
Explain how moving coil galvanometer is converted into a voltmeter. Derive the necessary formula.
A moving coil galvanometer has a resistance of 25Ω and gives a full scale deflection for a current of 10mA. How will you convert it into a voltmeter having range 0 - 100 V?
A galvanometer has a resistance of 16Ω. It shows full scale deflection, when a current of 20 mA is passed through it. The only shunt resistance available is 0.06 which is not appropriate to convert a galvanometer into an ammeter. How much resistance should be connected in series with the coil of galvanometer, so that the range of ammeter is 8 A?
Why is it necessary to introduce a radial magnetic field inside the coil of a galvanometer?
With the help of a neat and labelled diagram, explain the principle and working of a moving coil 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.
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?
State the underlying principle of working of a moving coil galvanometer. Write two reasons why a galvanometer can not be used as such to measure current in a given circuit. Name any two factors on which the current sensitivity of a galvanometer depends.
What are the advantages of using soft iron as a core, instead of steel, in the coils of galvanometers?
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 deflection in a moving coil galvanometer is ______.
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 ______.
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:
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:
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 ______.
Explain in brief the basic construction of a moving-coil table galvanometer whit a neat labelled diagram.
A resistance of 3Ω is connected in parallel to a galvanometer of resistance 297Ω. Find the fraction of current passing through the galvanometer.
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?
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:
Current sensitivity of a galvanometer is defined as the:
Voltage sensitivity of a galvanometer is defined as the:
The current sensitivity of a moving coil galvanometer is given by:
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:
At equilibrium, the deflecting and restoring torques acting on the coil of a moving coil galvanometer satisfy the condition:
The equilibrium condition \(NIAB = C\phi\) leads to the current–deflection relationship:
In a suspended-coil galvanometer, the phosphor-bronze strip serves to:
In the pivoted-coil (Weston) type galvanometer, the two hair springs:
The non-magnetic frame of a moving coil galvanometer is made of aluminium, and its function is to provide:
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:
