Extension of Ammeter and Voltmeter

Q. Three moving iron type voltmeters are connected as shown below. Voltmeter readings are $V,V_1$ and $V_2$ as indicated . The correct relation among the voltmeter readings is

1. $V=\frac{V_1}{\sqrt{2}}+\frac{V_2}{\sqrt{2}}$
2. $V=V_1+V_2$
3. $V=V_1{V}_2$
4. $V=V_2-V_1$

Q. A galvanometer with internal resistance $100\Omega$ and full-scale current 1 mA is used to realize a dc voltmeter with a full scale range of 1 V. The full scale range of this voltmeter can be extended to 10 V by connecting an external resistance of value

1. $9k\Omega$
2. $9.9k\Omega$
3. $10k\Omega$
4. $11k\Omega$

Q. A(0-50 A) moving coil ammeter has a voltage drop of 0.1 V across its terminals at full scale deflection. Then external shunt resistance (in milliohms) needed to extend its range to (0-500 A)is

1. 0.22

Q. A DC voltmeter has a sensitivity of $1000\Omega /volt.$ When it measures half of full scale in 100 V range, the current though the voltmeter is

1. $100mA$
2. $1mA$
3. $0.5mA$
4. $50mA$

Q. A full scale deflection current of a meter is 2 mA and its internal resistance is $500\Omega$. The instrument is required to be used as voltmeter with full scale deflection of 200 V. The value of series resistor required should be

1. $90.4k\Omega$
2. $99.5k\Omega$
3. $99.9k\Omega$
4. $90.4k\Omega$

Q. A $100\mu A$ ammeter has an internal resistance of $100\Omega$. For extending its range to measure $500\mu A$, the shunt resistance required is of

1. 20.0 $\Omega$
2. 22.22 $\Omega$
3. 25.0 $\Omega$
4. 50.0 $\Omega$

Q. A DC ammeter has a resistance of $0.1\Omega$ and its current range is $0-100A$. If the range is to be extended to $0-500A$, then meter requires the following shunt resistance

1. $0.010\Omega$
2. $0.011\Omega$
3. $0.025\Omega$
4. $1.0\Omega$

Q. The value of series resistance to be used to extend ( 0- 200) V range voltmeter having $2000\Omega /V$ sensitivity to be extended to ( 0-2000) V range.

1. $3600k\Omega$
2. $5500k\Omega$
3. $3400k\Omega$
4. $4500k\Omega$

Q. A 1000 V DC supply has two 1-core cables as its positive and negative leads: their insulation resistances to earth are $4M\Omega$ and$6M\Omega$, respectively, as shown in the figure. A voltmeter with resistance $50k\Omega$ is used to measure the insulation of the cable. When connected between the positive core and earth, then voltmeter reads

1. 8 V
2. 16 V
3. 24 V
4. 40 V

Q. When the voltage across a battery is measured using a dc potentiometer, the reading shows 1.08 V. But when the same voltage is measured using a Permanent Magnet Moving Coil (PMMC) voltmeter, the voltmeter reading shows 0.99 V. If the resistance of the voltmeter is $1100\Omega ,$ the internal resistance of the battery, in $\Omega$ is

1. 100