Question

You are sitting in a chamber with your back to B wall. An electron beam moving horizontally from wall B towards wall A. It is deflected by a strong magnetic field to your left side. What is direction of the magnetic field?

• A. Towards wall A
• B. Towards wall B
• C. Perpendicularly upwards
• D. Perpendicularly downwards

Answer 1

The correct option is C Perpendicularly upwards

Since the electron is moving from wall B to wall A, the direction of current will be towards wall B. The electron is deflected towards left hence by Fleming’s left hand rule the direction of magnetic field will be perpendicularly upwards.