Question

You need to produce a set of cylindrical copper wire 3.5 m long that will have a

Answer 1

Solution :

We know, resistance is given by :

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

$A = \dfrac{\rho l }{R}\\\\A = \dfrac{1.72\times 10^{-8} \times 3.5 }{0.125}\\\\A = 4.816 \times 10^{-7} \ m^2$

Now, we know mass of wire is given by :

$Mass = Density \times Volume\\\\\M = 8.9 \times 10^3 \times 4.816 \times 10^{-7} \times 3.5 kg\\\\M = 0.01500\ kg\\\\M = 15.00\ gram$

Hence, this is the required solution.