Question

If the area of an iron rod is 10 cm by 0.5 cm and length is 35 cm. Find the value of resistance, if 11x10^-8 ohm.m be the resistivity of iron.

Answer 1

Answer:

Resistance of the iron rod, R = 0.000077 ohms    

Explanation:

It is given that,

Area of iron rod, $A=10\ cm\times 0.5\ cm=5\ cm^2 = 0.0005\ m^2$

Length of the rod, L = 35 cm = 0.35 m

Resistivity of Iron, $\rho=11\times 10^{-8}\ \Omega-m$

We need to find the resistance of the iron rod. It is given by :

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

$R=11\times 10^{-8}\times \dfrac{0.35\ m}{0.0005\ m^2}$

$R=0.000077 \Omega$

So, the resistance of the rod is 0.000077 ohms. Hence, this is the required solution.