Question

resistivity of the material of a wire is 1.8 * 10^4 ohm. if diameter of its cross section area is 3 mm and length is 600 cm. calculate its resistance. ​

Answer 1

Answer:

The resistance of the material is $1.53*10^{10}$ Ω.

Explanation:

In an electrical circuit, resistance is a measure of the resistance to current flow. The unit of resistance is ohms.

Resistance R = $\frac{PL}{A}$

Where,

P = resistivity =  $1.8*10^{4}$Ωm

L = length = 600 cm = 6 m

A = area of cross section

Given that diameter d = 3 mm = $3*10^{-3}$ m

⇒radius r = $1.5*10^{-3}$ m

∴Area of cross-section of the wire = π$r^{2}$

                                                         = 3.14 × $(1.5*10^{-3} )^{2}$= $7.07*10^{-6}$$m^{2}$

⇒Resistance R = $\frac{PL}{A}$

                         = $\frac{1.8*10^{4} *6}{7.07*10^{-6} }$ = $1.53*10^{10}$ Ω

Therefore, the resistance of the material is $1.53*10^{10}$ Ω.