Advertisements
Advertisements
प्रश्न
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?
Advertisements
उत्तर
Resistance of the galvanometer coil, G = 15 Ω
Current for which the galvanometer shows full scale deflection, Ig = 4 mA = 4 × 10−3 A
Range of the ammeter is 0, which needs to be converted to 6 A.
∴ Current, I = 6 A
A shunt resistor of resistance S is to be connected in parallel with the galvanometer to convert it into an ammeter. The value of S is given as:
S = `("I"_"g""G")/("I" - "I"_"g")`
= `(4 xx 10^-3 xx 15)/(6 - 4 xx 10^-3)`
S = `(6 xx 10^-2)/(6 - 0.004)`
= `0.06/5.996`
≈ 0.01 Ω = 10 mΩ
Hence, a 10 mΩ shunt resistor is to be connected in parallel with the galvanometer.
APPEARS IN
संबंधित प्रश्न
The combined resistance of a galvanometer of resistance 500Ω and its shunt is 21Ω. Calculate the value of shunt.
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
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 ?
Explain, giving reasons, the basic difference in converting a galvanometer into (i) a voltmeter and (ii) an ammeter?
In the meter bridge experiment, balance point was observed at J with AJ = l.
(i) The values of R and X were doubled and then interchanged. What would be the new position of balance point?
(ii) If the galvanometer and battery are interchanged at the balance position, how will the alance point get affected?
What are the advantages of using soft iron as a core, instead of steel, in the coils of galvanometers?
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?
Define the term ‘current sensitivity’ of a moving coil galvanometer.
The deflection in a moving coil galvanometer is ______.
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:
The coil of galvanometer consists of 100 turns and effective area of 1 square cm. The restoring couple is 10-8 N-m/rad. The magnetic field between the pole pieces is 5T. The current sensitivity of this galvanometer will be ______.
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)
How is current sensitivity increased?
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 ______.
