Question

what is the resistance of a 20.0 meter long tungsten rod with a cross sectional area of 1.00 times 10^-4 meter^2 at 20C

Answer 1

Answer:

$0.0112 \Omega$

Explanation:

The resistance of an object tells us how much the object opposes to the flow of current through it.

The resistance of a conductor is given by the formula

$R=\frac{\rho L}{A}$

where

$\rho$ is the resistivity of the material

L is the length of the conductor

A is the cross-sectional area

For the tungsten rod in this problem, we have:

L = 20.0 m is the length

$A=1.00\cdot 10^{-4}m^2$ is the cross-sectional area

$\rho=5.6\cdot 10^{-8} \Omega \cdot m$ is the resistivity of tungsten at 20C

Substituting into the formula, we find the resistance of the tungsten rod:

$R=\frac{(5.6\cdot 10^{-8})(20.0)}{1.00\cdot 10^{-4}}=0.0112 \Omega$