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$$

The potentiometer wire AB is 600 cm long. At what distance from A should the jockey J touch the wire to get zero deflection in the galvanometer?

1. 320 cm

2. 120 cm

3. 20 cm

4. 450 cm

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?

    
1. Yes, \(\frac{P}{Q}=\frac{l_1-l_2}{l_1+l_2}\)
2. No, no null point
3. Yes, \(\frac{P}{Q}= \frac{l_2}{l_1}\)
4. Yes, \(\frac{P}{Q}= \frac{l_1}{l_2}\)

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:

In the figure below, what is the potential difference between the point A and B and between B and C, respectively, in steady state?

1. $V_{AB}=V_{BC}=100V$

2. $V_{AB}=75V,V_{BC}=25V$

3. $V_{AB}=25V,V_{BC}=75V$

4. $V_{AB}=V_{BC}=50V$

When the key K is pressed at time t = 0, which of the following statement about the current I in the resistor AB of the given circuit is true?
          

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. \(0.6~\Omega\)$\mathrm{}$

An ammeter A of finite resistance and a resistor R are joined in series to an ideal cell C. A potentiometer P is joined in parallel to R. The ammeter reading is ${\mathrm{I}}_0$ and the potentiometer reading is V₀ . P is now replaced by a voltmeter of finite resistance. The ammeter reading now is I and the voltmeter reading is V.

It can be concluded that:

1. $\mathrm{I}>{\mathrm{I}}_0,$ $\mathrm{V}<{\mathrm{V}}_0$

2. $\mathrm{I}>{\mathrm{I}}_0,$ $\mathrm{V}={\mathrm{V}}_0$

3. $\mathrm{I}={\mathrm{I}}_0,$ $\mathrm{V}<{\mathrm{V}}_0$

4. $\mathrm{I}<{\mathrm{I}}_0,$ $\mathrm{V}={\mathrm{V}}_0$