Current through wire XY of circuit shown is :

(1) 1 A

(2) 4 A

(3) 2 A

(4) 3 A

\(12\) cells each having the same emf are connected in series with some cells wrongly connected. The arrangement is connected in series with an ammeter and two similar cells which are in series. Current is \(3~\text{A}\) when cells and battery aid each other and is \(2~\text{A}\) when cells and battery oppose each other. The number of cells wrongly connected is/are:
1. \(4\)
2. \(1\)
3. \(3\)
4. \(2\)

Following figure shows cross-sections through three long conductors of the same length and material, with square cross-section of edge lengths as shown. Conductor B will fit snugly within conductor A, and conductor C will fit snugly within conductor B. Relationship between their end to end resistance is

(1) R_A = R_B = R_C

(2) R_A > R_B > R_C

(3) R_A < R_B < R

(4) Information is not sufficient

In the following star circuit diagram (figure), the equivalent resistance between the points A and H will be

(1) 1.944 r

(2) 0.973 r

(3) 0.486 r

(4) 0.243 r

In the adjoining circuit diagram each resistance is of 10 Ω. The current in the arm AD will be

1. $\frac{2i}{5}$

2. $\frac{3i}{5}$

3. $\frac{4i}{5}$

4. $\frac{i}{5}$

In the circuit of adjoining figure the current through 12 Ω resister will be

(1) 1 A

(2) $\frac{1}{5}A$

(3) $\frac{2}{5}A$

(4) 0 A

The reading of the ideal voltmeter in the adjoining diagram will be :

1. 4 V

2. 8 V

3. 12 V

4. 14 V

The resistance of the series combination of two resistance is S. When they are joined in parallel the total resistance is P. If S = nP, then the minimum possible value of n is :

(1) 4

(2) 3

(3) 2

(4) 1

A moving coil galvanometer has 150 equal divisions. Its current sensitivity is 10 divisions per milliampere and voltage sensitivity is 2 divisions per millivolt. In order that each division reads 1 volt, the resistance in ohms needed to be connected in series with the coil will be 

(1) 99995

(2) 9995

(3) 10³

(4) 10⁵

Which of the adjoining graphs represents ohmic resistance ?

(1)

(2)

(3)

(4)