When a wire of uniform cross-section a, length l and resistance R is bent into a complete circle, the resistance between any two of diametrically opposite points will be :

1. $\frac{R}{4}$

2. $\frac{R}{8}$

3. 4R

4. $\frac{R}{2}$ 

In the circuit given E = 6.0 V, R₁ = 100 ohms, R₂ = R₃ = 50 ohms, R₄ = 75 ohms. The equivalent resistance of the circuit, in ohms, is 

1. 11.875

2. 26.31

3. 118.75

4. None of these

By using only two resistance coils-singly, in series, or in parallel one should be able to obtain resistances of 3, 4, 12, and 16 ohms. The separate resistances of the coil are :

1. 3 and 4

2. 4 and 12

3. 12 and 16

4. 16 and 3

In the adjoining circuit, the battery E₁ 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 ohm is 

1. 10

2. 100

3. 500

4. 200

The magnitude and direction of the current in the circuit shown will be 

1. $\frac{7}{3}$A from a to b through e

2. $\frac{7}{3}$A from b to a through e

3. 1A from b to a through e

4. 1A from a to b through e

The e.m.f. of a cell is E volts and internal resistance is r ohm. The resistance in external circuit is also r ohm. The p.d. across the cell will be 

1. E/2

2. 2E

3. 4E

4. E/4

Kirchhoff's first law i.e. $\Sigma i=0$ at a junction is based on the law of conservation of :

1. Charge

2. Energy

3. Momentum

4. Angular momentum

The figure below shows currents in a part of electric circuit. The current i is

1. 1.7 amp

2. 3.7 amp

3. 1.3 amp

4. 1 amp

In the circuit shown, A and V are ideal ammeter and voltmeter respectively. Reading of the voltmeter will be

1. 2 V

2. 1 V

3. 0.5 V

4. Zero

The terminal potential difference of a cell when short-circuited is (E = E.M.F. of the cell)

1. E

2. E/2

3. Zero

4. E/3