Q. 134.1( 30 Votes )

The number density of free electrons in a copper conductor estimated in Example 3.1 is 8.5 × 1028 m–3. How long does an electron take to drift from one end of a wire 3.0 m long to its other end? The area of cross-section of the wire is 2.0 × 10–6 m2 and it is carrying a current of 3.0 A.

Answer :

Number density of free electrons in a copper conductor, n = 8.5 × 1028 per meter cube

Length of Copper Wire l = 3 meter


Area of cross section of wire A = 2 × 10-6 meter square


Current drawn by wire is given 3 Ampere


Since I = nAeVd


Here Vd is the drift velocity and “e” is the electron charge 1.6 × 10-19 Coulomb


And Vd Drift velocity is


Therefore


I = nAel/t


Or t = nAel/I



t = 2.7 × 104 second


Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
RELATED QUESTIONS :