A metallic wire of diameter 0.02m
contains 10^28 free electrons per cubic
meter. Find the drift velocity for
free electrons, having an electric
current of 100 amperes blowing
Through
the wire.
(Charge
on
electron = 1.6x10-19)
Answers
Answer:
I = Q / t charge / time = 100 Coul/sec
Q = d V = d A L where d is electrons / V volume, A area, L length
I = d A (L / t) = d A v whee v is the speed of the electrons
v = I / (d * A) speed of electrons
v = 100 Coul/sec / (1 * 10E28 electrons * 1.6 * 10E-19 Coul / electron / m^3 * .01 * pi m^2)
v = 100 /( 1 * 10E28 * 1.6 * 10E-19 * pi * .01^2) m/s
1.99 * 10E-4 = .199 mm / sec
(about 2 mm/sec)
Answer:
I = Q / t charge / time = 100 Coul/sec
Q = d V = d A L where d is electrons / V volume, A area, L length
I = d A (L / t) = d A v whee v is the speed of the electrons
v = I / (d * A) speed of electrons
v = 100 Coul/sec / (1 * 10E28 electrons * 1.6 * 10E-19 Coul / electron / m^3 * .01 * pi m^2)
v = 100 /( 1 * 10E28 * 1.6 * 10E-19 * pi * .01^2) m/s
1.99 * 10E-4 = .199 mm / sec
(about 2 mm/sec)