The resistance of a wire is \(R\) ohm. If it is melted and stretched to \(n\) times its original length, its new resistance will be:

1. \(nR\)

2. \(\frac{R}{n}\)

3. \(n^2R\)

4. \(\frac{R}{n^2}\)

Subtopic: Derivation of Ohm's Law |

82%

From NCERT

NEET - 2017

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

A wire made of a metal of uniform resistivity \(1.0\times 10^{-6}~\Omega{\text{-m}}\) is \(2.0~\text{m}\) long and has a diameter of \(2.0\times 10^{-3}~\text{m}\). What is the electrical resistance of this length of the wire?

1. \(\dfrac {2.0 ~\times~10^{-3}}{\pi} ~\Omega\)

2. \(5.0 ~\times~10^{-13}\pi~\Omega\)

3. \(\dfrac {1.0}{2\pi}~\Omega\)

4. \(\dfrac{2.0}{\pi}~\Omega\)

1. \(\dfrac {2.0 ~\times~10^{-3}}{\pi} ~\Omega\)

2. \(5.0 ~\times~10^{-13}\pi~\Omega\)

3. \(\dfrac {1.0}{2\pi}~\Omega\)

4. \(\dfrac{2.0}{\pi}~\Omega\)

Subtopic: Derivation of Ohm's Law |

82%

From NCERT

Please attempt this question first.

Hints

Please attempt this question first.

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 ${A}_{1}$ and the other one has a square cross-section of area ${A}_{2}$. The ratio ${A}_{1}/{A}_{2}$ is:

1. | \(1.5\) | 2. | \(1\) |

3. | \(0.8\) | 4. | \(2\) |

Subtopic: Derivation of Ohm's Law |

82%

From NCERT

NEET - 2020

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

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. | \(2~\Omega\) |

Subtopic: Derivation of Ohm's Law |

82%

From NCERT

AIPMT - 2013

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

The specific resistance of a conductor increases with:

1. | increase in temperature. |

2. | increase in cross-section area. |

3. | increase in cross-section and decrease in length. |

4. | decrease in cross-section area. |

Subtopic: Derivation of Ohm's Law |

79%

From NCERT

AIPMT - 2002

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

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. |

Subtopic: Derivation of Ohm's Law |

79%

From NCERT

NEET - 2022

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

The current-voltage graph for a given metallic conductor at two different temperatures \(T_{1}\) and \(T_{2}\) is as shown in the figure. Then:

1. \(T_{1}=T_{2}\)

2. \(T_{2}>T_{1}\)

3. \(T_{1}>T_{2}\)

4. nothing can be said

1. \(T_{1}=T_{2}\)

2. \(T_{2}>T_{1}\)

3. \(T_{1}>T_{2}\)

4. nothing can be said

Subtopic: Derivation of Ohm's Law |

75%

From NCERT

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

The dependence of resistivity \((\rho)\) on the temperature \((T)\) of a semiconductor is, roughly, represented by:

1. | 2. | ||

3. | 4. |

Subtopic: Derivation of Ohm's Law |

64%

From NCERT

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Two metal wires of identical dimensions are connected in series. If ${\mathrm{}}_{}$\(\sigma_1\)

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. | \(\frac{\sigma_1 \sigma_2}{\sigma_1+\sigma_2}\) |

Subtopic: Derivation of Ohm's Law |

63%

From NCERT

NEET - 2015

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Consider a thin rectangular sheet of side \(L,\) width \(b\) and thickness \(t,\) made of a material of resistivity \(\rho\). The resistance between two opposite faces, shown by the shaded areas in the figure is:

1. | directly proportional to \(b\) |

2. | inversely proportional to \(t\) |

3. | inversely proportional to \(L\) |

4. | both (1) and (2) |

Subtopic: Derivation of Ohm's Law |

64%

From NCERT

Please attempt this question first.

Hints

Please attempt this question first.