An aluminum wire having a cross-sectional area equal to 3.10 10-6 m2 carries a current of 5.50 A. The density of aluminum is 2.70 g/cm3. Assume each aluminum atom supplies one conduction electron per atom. Find the drift speed of the electrons in the wire.

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Explanation:

let's go through the calculations step by step:

Given:

Cross-sectional area of the wire, A = 3.10 * 10^-6 m^2

Current, I = 5.50 A

Density of aluminum, ρ = 2.70 g/cm^3

Charge of an electron, q = 1.6 * 10^-19 C

Step 1: Calculate the mass of the wire

Mass = density * volume

Volume = A * L, where L is the length of the wire

Let's assume the length of the wire, L = 1 m

Volume = (3.10 * 10^-6 m^2) * (1 m) = 3.10 * 10^-6 m^3

Mass = (2.70 g/cm^3) * (3.10 * 10^-6 m^3) = 8.37 * 10^-6 g

Step 2: Convert the mass to moles of aluminum

Molar mass of aluminum (Al) = 26.98 g/mol

Number of moles = mass / molar mass

Number of moles = (8.37 * 10^-6 g) / (26.98 g/mol) = 3.10 * 10^-7 mol

Step 3: Calculate the number of aluminum atoms

Avogadro's number = 6.022 * 10^23 atoms/mol

Number of aluminum atoms = number of moles * Avogadro's number

Number of aluminum atoms = (3.10 * 10^-7 mol) * (6.022 * 10^23 atoms/mol) = 1.87 * 10^17 atoms

Step 4: Calculate the number of conduction electrons

Since each aluminum atom contributes one conduction electron,

Number of conduction electrons = number of aluminum atoms * (1 electron/atom)

Number of conduction electrons = (1.87 * 10^17 atoms) * (1 electron/atom) = 1.87 * 10^17 electrons

Step 5: Calculate the drift velocity of the electrons

Drift velocity, v = I / (nAq), where n is the number of conduction electrons per unit volume

We are given the cross-sectional area, A, and the current, I, from which we have all the necessary values

v = (5.50 A) / ((1.87 * 10^17 electrons) * (3.10 * 10^-6 m^2) * (1.6 * 10^-19 C))

Calculating this expression will give us the drift velocity of the electrons in meters per second.