Question

A current of 2.4 a flows through cross sectional area 1.5 square millimeters. Find current density. If wire contains 8 free electrons per cubic meter calculate drift velocity of electrons

Answer 1

Answer:

2.4×1.5×8/1000=3.2×10^-4

Answer 2

Answer:

current density=1.6x10∧6 and drift velocity=1.25x10∧24

Explanation:

1.5mm∧2=1.5x10∧-6m∧2

current density=current/area= 2.4A/1.5x10∧-6m∧2

                                               = 1.6x10∧6A/m∧2

drift velocity= current density/(number of charge * elemental charge)

                    = 1.6x10∧6/(8 x 1.6x10∧-19C)

                    = 1.25x10∧24m/s