Voltmeter

Q. Voltmeters $V_1$ and $V_2$ are connected in series across a d.c. line. $V_1$ reads 80 V and has a per volt resistance of $200\Omega$, $V_2$ has a total resistance of $32k\Omega$. The line voltage is

1. 120 V
2. 160 V
3. 220 V
4. 240 V

Q. 100 mA current gives a full scale deflection in a galvanometer of resistance $2\Omega$. The resistance connected with the galvanometer to convert it into a voltmeter of 5 V range is

1. $98\Omega$
2. $52\Omega$
3. $80\Omega$
4. $48\Omega$

Q. To convert a galvanometer into a voltmeter, you have to

1. Change the dial markings on the galvanometer
2. Decrease its overall resistance
3. Increase its overall resistance
4. Use better batteries on it

Q. In given circuit when voltmeter is connected across $2\Omega$ gives reading 5V. When same voltmeter is connected across $3\Omega$ the reading will be

1. 5V
2. 7.5V
3. 2.5V
4. 4V

Q. In the following figure ammeter and voltmeter reads 2 amp and 120 volt respectively. Resistance of voltmeter is

1. $100\Omega$
2. $200\Omega$
3. $300\Omega$
4. $400\Omega$

Q. Voltmeter is connected in parallel to measure the potential difference across a component in a circuit.

1. False
2. True

Q. Voltmeter is connected in parallel to measure the potential difference across a component in a circuit.

1. False
2. True

Q. The magnitude of the resistance of the resistor in series with the coil of the voltmeter should be

1. Very High
2. Low
3. Medium
4. Negligible

Q. What is the equivalent resistance of a voltmeter with coil resistance $R_c=1k\Omega$ and series resistance of 100 k$\Omega$?

1. $101k\Omega$
2. $\frac{100}{101}k\Omega$
3. $\frac{101}{100}k\Omega$
4. $99k\Omega$

Q. How is the voltmeter connected with respect to the points where you want to measure the potential difference?

1. In series with the points
2. Between the points, in series.
3. Close to the points but not part of the circuit.
4. None of the above

Q. What is the current through the voltmeter if it has a coil resistance of 100k$\Omega$, series resistance of 1k$\Omega$ and 202V is measured by it?

1. 2A
2. 20mA
3. 2mA
4. 2.02A