A rod made up of metal is 1.2 m long and 0.8 cm in diameter. Its resistance is 3.5 10⁻³ . Another disc made of the same metal is 2.0 cm in diameter and 1.25 mm thick. What is the resistance between the round faces of the disc?

Step-by-step solution

Given, I=12 ~m , d=0.8 ~cm , R=3.5 10⁻³ , thickness =1.25 ~mm , Resistivity of the material of the rod aligned & = R A I = 3.5 10⁻³ (0.4 10⁻² )^2 1.2 & =46.6 10⁻⁹ m aligned aligned & Resistance of disc, R= (Thickness) Area of cross-section &= 46.6 10⁻⁹ (1.25 10⁻³ ) (1 10⁻² )^2 &= 5.82 10⁻⁷ aligned