Question

A vertical wire carrying a current in the upward direction is placed in a horizontal magnetic field directed towards north. The wire will experience a force towards :

• A. North
• B. South
• C. East
• D. West

Answer 1

The correct option is D West

The current carrying wire is shown in the figure.


Applying formula of magnetic force on current carrying wire,

$\overrightarrow{F}=i(\overrightarrow{L}\times \overrightarrow{B})$

By using the right-hand thumb rule, we get the direction of $\overrightarrow{F}$ towards west.

Hence, option $\left(D\right)$ is correct.

Why this question ? Tip: The direction of current in wire is taken as reference for deciding the direction of $\overrightarrow{L}$. Thus, $\overrightarrow{L}$ is in direction of current in wire.