What is the equivalent resistance between \(A\) and \(B\) in the figure below if \(R= 3~\Omega?\)
                    
1. \(9~\Omega\)
2. \(12~\Omega\)
3. \(15~\Omega\)
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:

The metre bridge shown is in a balanced position with \(\frac{P}{Q} = \frac{l_1}{l_2}\). If we now interchange the position of the galvanometer and the cell, will the bridge work? If yes, what will be the balanced condition?

The figure below shows currents in a part of the electric circuit. The current \(i\) is:

In the following circuit, the battery \(E_1\) has an emf of \(12\) volts and zero internal resistance while the battery \(E\) has an emf of \(2\) volts. If the galvanometer \(G\) reads zero, then the value of the resistance \(X\) in ohms is:

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 the 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 \(P,Q,R,S\)

A student has three \(6.0~\Omega\) resistors that can be connected together in any configuration. What are the maximum and minimum resistances that can be obtained by using one or more of these three resistors?
(Assume the connections between the resistors have negligible resistance, the temperature of the resistors is constant, and the resistors are used in a d.c. circuit and none of the resistors are short-circuited.)

Three resistors are connected to a \(20\) V battery with a constant voltage supply. One of the resistors is a variable resistor. The resistance of the variable resistor is gradually increased from \(0~\Omega\) to \(5\) \(\Omega.\)
   

Which graph correctly represents how the current drawn from the battery varies with the resistance \((R)\) of the variable resistor?

1.		2.
3.		4.

A voltmeter of resistance \(660~\Omega\)$\mathrm{}$ 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. \(30~\Omega\)$\mathrm{}$ 
2. \(60~\Omega\)
3. \(6~\Omega\)
4. \(0.6~\Omega\)$\mathrm{}$