Gold is the most ductile of all metals. for example, one gram of gold can be drawn into a wire 2.05 km long. the density of gold is 19.3 ✕ 10^3 kg/m^3, and its resistivity is 2.44 ✕ 10^−8 ω · m. what is the resistance of such a wire at 20.0°c?

Resistance of gold wire,

Explanation:

In this question we have given

Density of gold,

resistivity of gold,

Length of wire,

Temperature,

We know that relation between volume and density is given as

Therefore, volume occupied by one gram gold is given as,

.........(1)

We Know that Volume of gold wire which is cylindrical in shape is given by following formula

......(2)

Here,

...........(3)

here A is the cross sectional area of cylendrical gold wire  

From equation 2 and 3

we got

...............(4)

on comparing equation 1 and equation 4, we got,

we know that resistance and resistivity are related by following formula,

................(5)

Put values of resistivity, A and L in equation 5, we got

Therefore resistance of gold wire,

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