The drift velocity of free electrons in a conductor is \(v\) when a current \(i\) is flowing in it. If both the radius and current are doubled, then the drift velocity will be:
1. \(v\)
2. \(\frac{v}{2}\)
3. \(\frac{v}{4}\)
4. \(\frac{v}{8}\)
A battery has e.m.f. 4 V and internal resistance r. When this battery is connected to an external resistance of 2 ohm, a current of 1 ampere flows in the circuit. How much current will flow if the terminals of the battery are connected directly?
1. | 1 A | 2. | 2 A |
3. | 4 A | 4. | Infinite |
The equivalent resistance between \(A\) and \(B\) is:
1. \(3~\Omega\)
2. \(6~\Omega\)
3. \(9~\Omega\)
4. \(12~\Omega\)
The current I as shown in the circuit will be:
1. 10 A
2.
3.
4.
The current through the 5 resistor is:
1. 3.2 A
2. 2.8 A
3. 0.8 A
4. 0.2 A
The current in a wire varies with time according to the relation i= (3+2t) A. The amount of charge passing a cross section of the wire in the time interval t=0 to t=4.0 sec would be: (where t is time in seconds)
1. | 28 C | 2. | 30.5 C |
3. | 8 C | 4. | 82 C |
In the circuit shown, the value of each of the resistances is r. The equivalent resistance of the circuit between terminals A and B will be:
1. (4/3)r
2. 3r/2
3. r/3
4. 8r/7
Drift velocity vd varies with the intensity of electric field as per the relation:
1.
2.
3. vd = constant
4.
If a metallic block has no potential difference applied across it, then the mean velocity of free electron is:
(T = absolute temperature of the block)
1. | proportional to T. | 2. | proportional to\(\sqrt{\mathrm{T}} \) |
3. | zero. | 4. | finite but independent of temperature. |
A wire of resistance R is divided into 10 equal parts. These parts are connected in parallel, the equivalent resistance of such connection will be:
1. 0.01R
2. 0.1R
3. 10R
4. 100R