The external diameter of 5 ~m long hollow tube is 0.1 ~m and thickness of its wall is 0.005 ~m . If =1.7 10⁻⁸ - m , then its resistance will be

Step-by-step solution

Given, Iength, l=5 ~m External diameter, d₁=0.1 ~m External radius, r₁= d₁ 2 = 0.1 2 =0.05 ~m Thickness, t=0.005 ~m Internal radius, r₂=r₁-t =0.05-0.005=0.045 ~m Area of cross-section of hollow tube, aligned A & = (r₁^2-r₂^2 ) & =3.14 [(0.05)^2-(0.045)^2 ] & =3.14 4.75 10⁻⁴ & =14.915 10⁻⁴=1.49 10⁻³ ~m ^2 aligned Resistance, R= l A =1.7 10⁻⁸ 5 1.49 10⁻³ =5.7 10⁻⁵