Building codes usually limit the current carried by a no. 14 copper wire to 15 a. many household circuits are wired with this size wire. what is the drift velocity of the electrons in this case? the diameter of no. 14 wire is 1.6 mm. assume one conduction electron per atom in copper. the atomic weight of copper is 63.3 and its density is 8900 kg/m3.

a. 4.89 x 10-5 m/s
b. 4.56 x 10-4 m/s
c. 5.52 x 10-4 m/s
d. 4.44 x 10-2 m/s
e. 1.65 x 10-3 m/s

The drift velocity of the electrons in this case is c) 5.52 x 10-4 m/s

Explanation:

Hi

First of all, we need to find the volume occupied by 63.3g of copper, so , then if we assume each atom of copper contributes with one free electron to the material body .

Finally, we apply , where A is area so, , thus .

As we can see c. 5.52 x 10-4 m/s is the nearest one.

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day