A 5.0 A electric current passes through an aluminum wire of 4.0~\times~10^{-6}~m^2 cross-sectional area. Aluminum has one free electron per atom. The density of aluminum is 2.7~grams/cm^3, and the aluminum molar mass is 27 g. What is the electron number density (the number of electrons per unit volume) in the wire

The electron number density (the number of electrons per unit volume) in the wire is .

Explanation:

Given: Current = 5.0 A

Area =

Density = 2.7 , Molar mass = 27 g

The electron density is calculated as follows.

where,

= density

M = molar mass

= Avogadro's number

Substitute the values into above formula as follows.

Thus, we can conclude that the electron number density (the number of electrons per unit volume) in the wire is .