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A galvanometer with a coil of resistance 40 Ω gives a full scale deflection for a current of  5 mA. How will you convert it into an ammeter of range 0-5A?

Important Questions on Moving Charges and Magnetism

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Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
A 50 Ω resistance is connected to a battery of 5 V. A galvanometer of resistance 100 Ω is to be used as an ammeter to measure current through the resistance, for this a resistance rS is connected to the galvanometer. Which of the following connections should be employed if the measured current is with in 1% of the current without the ammeter in the circuit?
EASY
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
A galvanometer with its coil resistance 25 Ω requires a current of 1 mA for its full deflection. In order to construct an ammeter to read up to a current of 2 A the approximate value of the shunt resistance should be:
MEDIUM
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments

A galvanometer has a 50 division scale. Battery has no internal resistance. It is found that there is deflection of 40 divisions when R.B.=2400 Ω. Deflection becomes 20 divisions when resistance taken from resistance box is 4900 Ω. Then we can conclude :

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Note: This question is awarded as the bonus. Now the question is corrected.

MEDIUM
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
The range of an ammeter of resistance G can be increased from I to nI by connecting
MEDIUM
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
How is a galvanometer converted to an ammeter?
MEDIUM
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
In an ammeter 0.2% of main current passes through the galvanometer. If resistance of galvanometer is G, the resistance of ammeter will be:
HARD
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
In a circuit for finding the resistance of a galvanometer by half deflection method, a 6 V battery and a high resistance of 11 kΩ are used. The figure of merit of the galvanometer is 60 μA division-1. In the absence of shunt resistance, the galvanometer produces a deflection of θ=9 divisions when current flows in the circuit. The value of the shunt resistance that can cause the deflection of θ2, is closest to:
MEDIUM
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
A millivoltmeter of 25 mV range is to be converted into an ammeter of 25 A range. The value (in ohm) of necessary shunt will be
MEDIUM
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments

Derive the expression for the torque acting on the rectangular current carrying coil of a galvanometer. Why is the magnetic field made radial?

EASY
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
Define current sensitivity of a galvanometer. Write its expression.
EASY
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
An ammeter of resistance 1.5 Ω can measure currents upto 1 A. The value of shunt resistance to measure current upto 4 A is
MEDIUM
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments

How do you convert a moving coil galvanometer into an ammeter?

MEDIUM
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
A galvanometer of resistance 100 Ω requires 10 μA current for full scale deflection. Now a resistance of 1 Ω is connected to convert it into an ammeter. The minimum current required to obtain full scale deflection is
HARD
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
A moving coil galvanometer, having a resistance G, produces full scale deflection when a current IG flows through it. This galvanometer can be converted into (i) an ammeter of range 0 to IoI0>Ig by connecting a shunt resistance RA to it and (ii) into a voltmeter of range 0 to VV=GI0 by connecting a series resistance RV to it. Then,
EASY
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
A 50 ohm galvanometer gets full scale deflection when a current of 0.01 A pass through the coil. When it is converted to a 10 A ammeter, the shunt resistance is
EASY
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
This question has Statement I and Statement II. Of the four choices given after the Statements, choose the one that best describes the two Statements.

Statement - I : Higher the range, greater is the resistance of ammeter.
Statement - II : To increase the range of ammeter, additional shunt needs to be used across it.
MEDIUM
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
A galvanometer, whose resistance is 50 ohm , has 25 divisions in it. When a current of 4×10-4 A passes through it, its needle (pointer) deflects by one division. To use this galvanometer as a voltmeter of range 2.5 V it should be connected to a resistance of:
EASY
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
A circuit contains an ammeter, a battery of 30 v and a resistance 40.8 ohm all connected in series. If the ammeter has coil of resistance 480 ohm and a shunt of 20 ohm, the reading in the ammeter will be:
MEDIUM
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments

Distinguish between ammeter and voltmeter.

EASY
Physics>Electricity and Magnetism>Moving Charges and Magnetism>Electrical Instruments
When a current of  5 mA is passed through a galvanometer having a coil of resistance 15 Ω, it shows full-scale deflection. The value of the resistance to be put in series with the galvanometer to convert it into a voltmeter of range 0-10 V is: