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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CBSE CLASS XII Related Questions

1.
Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.

4.
If T is the time period of the rotation of the coil, at what values of t in a cycle, the emf generator is maximum ?

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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.Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.

4.If T is the time period of the rotation of the coil, at what values of t in a cycle, the emf generator is maximum ?

Similar Physics Concepts

Comments

SUBSCRIBE TO OUR NEWS LETTER

1.
Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.

4.
If T is the time period of the rotation of the coil, at what values of t in a cycle, the emf generator is maximum ?