Question

A Copper wire of resistivity 1.6 × 10^-8 ohm has a cross sectional area of 20 × 10^-4 cm^2. Calculate the length of this wire required to make 10 ohm coil.​

Answer 1

Answer:

1.25×10^6cm

Explanation:

resistivity of copper wire=1.6×10^-8ohm cm

area of copper wire = 20×10^-4cm²

resistance = 10ohm

as we know,,

resistance = resistivity×length/area

so, acc. to question,,

10 = (1.6×10^-8×l)/(20×10^-4)

so, l = (10×20×10^-4)/(1.6×10^-8)

= 2/16×10^7

= 0.125×10^7

=> 1.25×10^6cm ....ans.