MCQ
A current $I$ is passing through a wire having two sections $P$ and $Q$ of uniform diameters $d$ and $d/2$ respectively. If the mean drift velocity of electrons in sections $P$ and $Q$ is denoted by $v_P$ and $v_Q$ respectively, then
- A$v_P = v_Q$
- B$v_P = \frac{1}{2}v_Q$
- ✓$v_P = \frac{1}{4}v_Q$
- D$v_P = 2 v_Q$
