1. | \((3\times 10^{-1})^\circ \text{C}^{-1}\) | 2. | \((3 \times 10^{-4})^\circ \text{C}^{-1}\) |
3. | \((3 \times 10^{-3})^\circ \text{C}^{-1}\) | 4. | \((3 \times 10^{-2})^\circ \text{C}^{-1}\) |
1. | Germanium | 2. | Silver |
3. | Glass | 4. | Silicon |
1. | \(81\) \(\Omega\) | 2. | \(9\) \(\Omega\) |
3. | \(729\) \(\Omega\) | 4. | \(243\) \(\Omega\) |
The plot of current \(I~\text{(A)}\) flowing through a metallic conductor versus the applied voltage \(V~\text{(volt)}\) across the ends of a conductor is:
1. | 2. | ||
3. | 4. |
1. | reactance | 2. | mobility |
3. | conductivity | 4. | conductance |
Which of the following graph represents the variation of resistivity () with temperature (\(T\)) for copper?
1. | 2. | ||
3. | 4. |
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. | \(2\) |
Two metal wires of identical dimensions are connected in series. If \(\sigma_1\)
1. | \(\frac{2\sigma_1 \sigma_2}{\sigma_1+\sigma_2}\) | 2. | \(\frac{\sigma_1 +\sigma_2}{2\sigma_1\sigma_2}\) |
3. | \(\frac{\sigma_1 +\sigma_2}{\sigma_1\sigma_2}\) | 4. | \(\frac{\sigma_1 \sigma_2}{\sigma_1+\sigma_2}\) |
A wire of resistance \(4~\Omega\) is stretched to twice its original length. The resistance of a stretched wire would be:
1. \(4~\Omega\)
2. \(8~\Omega\)
3. \(16~\Omega\)
4. \(2~\Omega\)
A 6-volt battery is connected to the terminals of a three-metre-long wire of uniform thickness and resistance of 100 ohms. The difference of potential between two points on the wire separated by a distance of 50 cm will be:
1. 3 V
2. 1 V
3. 1.5 V
4. 2 V