question_answer 10)

Imagine that you are sitting in a chamber with your back to one wall. An electron beam, moving horizontally from back wall towards the front wall, is deflected by a strong magnetic field to your right side. What is the direction of the magnetic field?

Answer:

The direction of current I is opposite to the direction electron beam as shown in figure. Since the beam is deflected to the right side, the force, F acting on the beam is as shown.  Applying Fleming's left hand rule, it is found that magnetic field, B is acting vertically downwards (i.e., perpendicular to the plane of the paper and directed inwards) as shown by.