9.0×1015 electrons flow through a cross section of silver wire in 290 μs with a drift speed of 9.0×10−4 m/s .

Question

What is the diameter of the wire?

Answer 1

Step 1:

The number of electrons are .

The drift speed is .

The time is .

The electron number density of silver is .

The number of charge carriers in a volume element is .

.

The circular cross sectional area is .

Substitute in .

.

Step 2:

Find the diameter of the wire.

Substitute , , and in .

.

The diameter of the wire is .

Solution:

The diameter of the wire is .