Twelve wires of equal resistance R are connected to form a cube. The effective resistance between two diagonal ends A and E will be:
1.
2.
3.
4.
A constant voltage is applied between the two ends of a uniform metallic wire. Some heat is developed in it. The heat developed doubles if:
1. | both the length and the radius of the wire are halved. |
2. | both the length and the radius of the wire are doubled. |
3. | the radius of the wire is doubled. |
4. | The length of the wire is doubled. |
Kirchhoff's junction rule is a reflection of:
a. | conservation of the current density vector |
b. | conservation of charge |
c. | the fact that the momentum with which a charged particle approaches a junction is unchanged (as a vector) as the charged particle leaves the junction |
d. | the fact that there is no accumulation of charges at a junction |
Which of the above statements are correct?
1. b and c
2. a and c
3. b and d
4. c and d
A charged particle having drift velocity of \(7.5\times10^{-4}~\text{ms}^{-1}\) in an electric field of \(3\times10^{-10}~\text{Vm}^{-1}\), has mobility of:
1. \(2.5\times 10^{6}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)
2. \(2.5\times 10^{-6}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)
3. \(2.25\times 10^{-15}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)
4. \(2.25\times 10^{15}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)
For the circuit shown in the figure, the current \(I\) will be:
1. \(0.75~\text{A}\)
2. \(1~\text{A}\)
3. \(1.5~\text{A}\)
4. \(0.5~\text{A}\)
Two solid conductors are made up of the same material and have the same length and the same resistance. One of them has a circular cross-section of area and the other one has a square cross-section of area . The ratio is:
1. | \(1.5\) | 2. | \(1\) |
3. | \(0.8\) | 4. | \(2\) |
For the circuit given below, Kirchhoff's loop rule for the loop \(BCDEB\) is given by the equation:
1. | \(-{i}_2 {R}_2+{E}_2-{E}_3+{i}_3{R}_1=0\) |
2. | \({i}_2{R}_2+{E}_2-{E}_3-{i}_3 {R}_1=0\) |
3. | \({i}_2 {R}_2+{E}_2+{E}_3+{i}_3 {R}_1=0\) |
4. | \(-{i}_2 {R}_2+{E}_2+{E}_3+{i}_3{R}_1=0\) |
The equivalent resistance between \(A\) and \(B\) for the mesh shown in the figure is:
1. | \(7.2\) \(\Omega\) | 2. | \(16\) \(\Omega\) |
3. | \(30\) \(\Omega\) | 4. | \(4.8\) \(\Omega\) |
When a 100 W, 240 V bulb is operated at 200 volt, the current in it is:
1. 0.35 A
2. 0.42 A
3. 0.50 A
4. 0.58 A
For the given circuit, the value of the resistance in which the maximum heat is produced is:
1. 2
2. 6
3. 4
4. 12