Advertisements
Advertisements
प्रश्न
Explain, giving reasons, the basic difference in converting a galvanometer into (i) a voltmeter and (ii) an ammeter?
Advertisements
उत्तर
(i) In converting a galvanometer into a voltmeter, a very high suitable resistance is connected is series to its coil. So, the galvanometer gives full scale deflection.
(ii) In converting a galvanometer into an ammeter, a very small suitable resistance is connected in parallel to its coil. The remaining pair of the current i.e. (I − Ig) flows through the resistance. Here I = Circuit current
Ig = Current through galvanometer
संबंधित प्रश्न
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
Two moving coil meters, M1 and M2 have the following particulars:
R1 = 10 Ω, N1 = 30,
A1 = 3.6 × 10–3 m2, B1 = 0.25 T
R2 = 14 Ω, N2 = 42,
A2 = 1.8 × 10–3 m2, B2 = 0.50 T
(The spring constants are identical for the two meters.)
Determine the ratio of
- current sensitivity and
- voltage sensitivity of M2 and M1.
Explain how moving coil galvanometer is converted into a voltmeter. Derive the necessary formula.
With the help of a neat and labelled diagram, explain the principle and working of a moving coil galvanometer ?
What are the advantages of using soft iron as a core, instead of steel, in the coils of galvanometers?
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.
The figure below shows a circuit containing an ammeter A, a galvanometer G and a plug key K. When the key is closed:
The current sensitivity of a moving coil galvanometer is given by:
The voltage sensitivity of a moving coil galvanometer, where G is the resistance of the galvanometer coil, is given by:
In a suspended-coil galvanometer, the phosphor-bronze strip serves to:
