Question

An electron enters a magnetic field at right angle to it, as shown in the figure. The direction of force acting on the electron will be -

• A. to the right.
• B. to the left.
• C. out of the page.
• D. into the page.

Answer 1

The correct option is D into the page.


The direction of current is opposite to the direction of motion of the electron.

According to Fleming's left-hand rule, pointing forefinger in the direction of magnetic field, middle finger in the direction of current, the thumb which is pointing into the page in this case gives the force direction.

Therefore, the direction of force acting on the electron will be into the page.

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