Physics

Problem

A copper wire of radius

0.50\,\text{mm}

carries a steady current of

3.0\,\text{A}

. The number density of free electrons in copper is

8.5 \times 10^{28}\,\text{m}^{-3}

and the elementary charge is

1.6 \times 10^{-19}\,\text{C}

. a. (i) Calculate the drift velocity of the electrons in the wire. b. (ii) Hence determine the time taken by an electron to drift a distance of

2.0\,\text{cm}

along the wire.