A voltmeter of resistance \(660~\Omega\) reads the voltage of a very old cell to be \(1.32\) V while a potentiometer reads its voltage to be \(1.44\) V. The internal resistance of the cell is:
1. \(30~\Omega\)
2. \(60~\Omega\)
3. \(6~\Omega\)
4. \(0.6~\Omega\)
In the following circuit, the battery has an e.m.f of 12 volts and zero internal resistance while the battery E has an e.m.f of 2 volts. If the galvanometer G reads zero, then the value of the resistance X in ohms is:
1. 10
2. 100
3. 500
4. 200
The figure below shows currents in a part of the electric circuit. The current \(i\) is:
1. \( 1.7 \mathrm{~A} \)
2. \( 3.7 \mathrm{~A} \)
3. \( 1.3 \mathrm{~A} \)
4. \( 1 \mathrm{~A}\)
What is the equivalent resistance between A and B in the figure below if R = 3 ?
1. 9
2. 12
3. 15
4. None of these
A torch bulb rated 4.5 W, 1.5 V is connected as shown in the figure below. The emf of the cell needed to make the bulb glow at full intensity is:
1. 4.5 V
2. 1.5 V
3. 2.67 V
4. 13.5 V
What is total resistance across terminals A and B in the following network?
1. R
2. 2R
3.
4.
The current in a wire varies with time according to the equation \(I=(4+2t),\) where \(I\) is in ampere and \(t\) is in seconds. The quantity of charge which has passed through a cross-section of the wire during the time \(t=2\) s to \(t=6\) s will be:
1. | \(60\) C | 2. | \(24\) C |
3. | \(48\) C | 4. | \(30\) C |
Figure (a) below shows a Wheatstone bridge in which P, Q R, S are fixed resistances, \(G\) is a galvanometer, and \(B\) is a battery. For this particular case, the galvanometer shows zero deflection. Now, only the positions of \(B\) and \(G\) are interchanged. as shown in figure (b). The new deflection of the galvanometer:
1. | is to the left |
2. | is to the right |
3. | is zero |
4. | depends on the values of P, Q, R, S |
An electric heater consists of a nichrome coil and runs under \(220\) V, consuming \(1\) kW of power. Part of its coil burned out and it was reconnected after cutting off the burnt portion. The power it will consume now is:
1. | more than \(1\) kW |
2. | less than \(1\) kW but not zero |
3. | \(1\) kW |
4. | \(0\) |
The circuit shown contains three identical resistors, two ammeters X and Y, and a voltmeter Z. The internal resistance of the battery is negligible.
Which option shows the readings on the three meters?
(Assume the ammeters have negligible resistance, and negligible current flows through the voltmeter.)
1. | X = \(1.0\) A; Y = \(0.0\) A; Z = \(12\) V |
2. | X = \(2.0\) A; Y = \(0.0\) A; Z = \(4.0\) V |
3. | X = \(1.0\) A; Y = \(2.0\) A; Z = \(8.0\) V |
4. | X = \(3.0\) A; Y = \(6.0\) A; Z = \(12\) V |