The current in the branch AB in the given network is:

 
1. 5/8 A

2. 5/2 A

3. 15/8 A

4. 3/2 A

The four arms of a Wheatstone bridge have the following resistances as shown in the figure. A galvanometer of 15Ω resistance is connected across BD. What is the current through the galvanometer when a potential difference of 10 V is maintained across AC?

1. 4.87 mA

2. 3.72 mA

3. 5.01 mA

4. 2.65 mA

In a meter bridge (shown in the figure), the null point is found at a distance of \(33.7\text{ cm}\) from \(A.\) If now a resistance of \(12~\Omega\) is connected in parallel with \(S,\) the null point occurs at \(51.9\text{ cm}.\) The values of \(R\) and \(S\) are respectively:

  
1. \(13.5~\Omega,~6.86~\Omega\)
2. \(13.5~\Omega,~13.5~\Omega\)
3. \(6.86~\Omega,~6.86~\Omega\)
4. \(6.86~\Omega,~13.5~\Omega\)

A resistance of $R<mspace\; width="1em"></mspace>\Omega$ draws current from a potentiometer. The potentiometer has a total resistance $R_0<mspace\; width="1em"></mspace>\Omega$  (as shown in the figure). A voltage V is supplied to the potentiometer. What is the voltage across R when the sliding contact is in the middle of the potentiometer?

$1.<mspace\; width="1em"></mspace>\frac{2VR}{R_0+4R}$
$2.<mspace\; width="1em"></mspace>\frac{VR}{R_0+4R}$
$3.<mspace\; width="1em"></mspace>\frac{2VR}{R_0+2R}$
$4.<mspace\; width="1em"></mspace>\frac{VR}{R_0+2R}$

A light bulb is rated at \(100~\text {W}\) for a \(220~\text {V}\) supply, the resistance of the bulb is:$\mathrm{}$
1. \(423~\Omega\)
2. \(440~\Omega\)
3. \(444~\Omega\)
4. \(484~\Omega\)

Which one of the following is correct?

The curve in the given graph shows the variation of potential difference 'V' across a conductor with current 'I' flowing through a conductor. The dashed line in the graph given below represents:

1. A non-ohmic conductor

2. An ohmic conductor

3. A semiconductor

4. An insulator

Graph shows the variation of resistivity$\left(\rho \right)$ with temperature for a material. The material can be-

1. Copper

2. Aluminum

3. GaAs

4. Nichrome

Match Column-I and Column-II with appropriate relations.

In a potentiometer circuit, a cell of emf \(1.5~\text{V}\) gives a balance point at 36 cm length of wire. If another cell of emf 2.5 V replaces the first cell, then at what length of the wire, the balance point occur? 
1. 64 cm 
2. 62 cm 
3. 60 cm 
4. 21.6 cm