A conductor has a diameter of

1.00mm and length 2.00m the
resistance of the material is 0.1Ω,
its resistivity is___
A. 3.93 x 10-6 Ωm
B. 2.55 x 102 Ωm
C. 3.93 x 10-8 Ωm
D. 2.55 x 102 Ωm

1 answer

To find the resistivity (ρ) of the material, we can use the formula:

ρ = (R * A) / L

where R is the resistance, A is the cross-sectional area of the conductor, and L is the length of the conductor.

First, we need to find the cross-sectional area (A) of the conductor. The formula for the area of a circle is:

A = π * r^2

where r is the radius of the circle. The radius can be found by dividing the diameter by 2:

r = 1.00mm / 2 = 0.5mm = 0.0005m

Now we can find the cross-sectional area:

A = π * (0.0005m)^2 = 0.0000007854 m^2

Next, we can substitute the values into the formula for resistivity:

ρ = (0.1Ω * 0.0000007854 m^2) / 2.00m

Simplifying this expression gives:

ρ = 0.00000007854 Ωm

Therefore, the resistivity of the material is 7.854 x 10^-8 Ωm.

The closest answer choice is C. 3.93 x 10^-8 Ωm.