Question

A wire 7ohm/metre is turned in the form of a circle of the diameter 2metre.Find the resistance across the ends of the diameter

Answer 1

Answer: The resistance across the ends of the diameter is 4.5 ohm.

Explanation:

Given that,

Resistivity $\rho = 7\ \Omega/m$

Diameter d = 2 meter

We know that,

The resistance is the product of the resistivity of the wire and length of the wire divided by the area of the wire.

$R = \dfrac{\rho l}{A}$

$R = \dfrac{7\times 2}{3.14\times1}$

$R = 4.5\ \Omega$

Hence, The resistance across the ends of the diameter is 4.5 ohm.