Two copper wires, of 1 m and 9 m respectively, have same resistance. Find their diameters in ratio.

The electrical resistance an electrical conductor has is known as the resistance to the passage of electric current via it.

A wire’s resistance is inversely proportional to area of the wire’s cross-section. It is also directly proportional to the wire’s length.
In case the diameter of wire increases, while length of the wire decreases, then the resistance of the wire lowers. Thus, as the diameter of the wire decreases while length of the wire increases, then the resistance of the wire increases.

The resistance of the conductor can be expressed as:

R = ρ l/A

Herein, the wire is 9 times longer than the first one. The resistance simultaneously increases as the length expands. Since the diameter of the wire is inversely linked to the resistance, it can be increased in order to maintain equivalent resistance. Now, since the area of the cross-section is considered proportional to the diameter, the resistance will be constant when diameter of the wire will be increased by three times.

Thus, their diameters will be in the 1:3 ratio.

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Two copper wires, of 1 m and 9 m respectively, have same resistance. Find their diameters in ratio.

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2.
In a Young's double-slit experiment, two waves each of intensity I superpose each other and produce an interference pattern. Prove that the resultant intensities at maxima and minima are 4I and zero respectively.

4.
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Two copper wires, of 1 m and 9 m respectively, have same resistance. Find their diameters in ratio.

Related Questions

CBSE CLASS XII Related Questions

1.Assertion : Induced emf produced in a coil will be more when the magnetic flux linked with the coil is more. Reason (R): Induced emf produced is directly proportional to the magnetic flux.

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4.The figure represents the variation of the electric potential \( V \) at a point in a region of space as a function of its position along the x-axis. A charged particle will experience the maximum force at:

5.Light of which of the following colours will have the maximum energy in a photon associated with it?

6.Assertion : In Young’s double-slit experiment, the fringe width for dark and bright fringes is the same. Reason (R): Fringe width is given by \( \beta = \frac{\lambda D}{d} \), where symbols have their usual meanings.

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Comments

SUBSCRIBE TO OUR NEWS LETTER

1.
Assertion : Induced emf produced in a coil will be more when the magnetic flux linked with the coil is more. Reason (R): Induced emf produced is directly proportional to the magnetic flux.

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In a Young's double-slit experiment, two waves each of intensity I superpose each other and produce an interference pattern. Prove that the resultant intensities at maxima and minima are 4I and zero respectively.

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The figure represents the variation of the electric potential \( V \) at a point in a region of space as a function of its position along the x-axis. A charged particle will experience the maximum force at:

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Light of which of the following colours will have the maximum energy in a photon associated with it?

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