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

1. R/2

2. R/4

3. R/8

4. 4R

For the network shown in the figure below, the value of the current \(i\) is:

     
1. \(\frac{18V}{5}\)
2. \(\frac{5V}{9}\)
3. \(\frac{9V}{35}\)
4. \(\frac{5V}{18}\)

A car battery of emf \(12~\text{V}\) and internal resistance \(5\times 10^{-2}~\Omega\) receives a current of \(60~\text{A}\) from an external source. The terminal voltage of the battery is:

If there are two bulbs of \((40~\text{W},200~\text{V}),\) and \((100~\text{W},200~\text{V}),\) then the correct relation for their resistance is:
1. \(R_{40}<R_{100}\)
2. \(R_{40}>R_{100}\)
3. \(R_{40}=R_{100}\)
4. no relation can be predicted

When three identical bulbs are connected in series, the consumed power is \(10\) W. If they are now connected in parallel then the consumed power will be:
1. \(30\) W
2. \(90\) W
3. \(\frac{10}{3}\) W
4. \(270\) W

According to the Faraday Law of electrolysis, the mass deposited at electrode will be proportional to:

1. m ∝ I²

2. m ∝ Q

3. m ∝ Q²

4. 'm' does not depend on Q

In a hot wire ammeter due to the flowing of the current, the temperature of the wire is increased by \(5^{\circ}\) C. If the value of the current is doubled, then the increase in temperature will be:
1. \(15^{\circ}\) C
2. \(20^{\circ}\) C
3. \(25^{\circ}\) C
4. \(30^{\circ}\) C

The potentiometer is best for measuring voltage, as:

1. It has a sensitive galvanometer
2. It has wire of high resistance
3. It measures p.d. like in closed circuit
4. It measures p.d. like in open circuit

When three identical bulbs of \(60~\text{watts}\) and \(200~\text{volt}\) rating are connected in series to a \(200~\text{volt}\) supply, the power drawn by them will be:
1. \(180~\text{watt}\)
2. \(10~\text{watt}\)
3. \(20~\text{watt}\)
4. \(60~\text{watt}\)

The electric resistance of a particular wire of iron is \(R.\) If its length and radius are doubled, then: