Chapter 24, Problem 90A

To determine

The direction of the magnetic field when the charged particle moves from back to front of the room experiencing an upward force by the magnetic field.

Explanation of Solution

Introduction:

A charge put in a magnetic field experiences force. The direction of the force on the charge can be determined by Fleming’s left hand rule.

The direction of the force experienced by a charged particle in a magnetic field is determined by Fleming’s left hand rule as shown above. According to this, the velocity is from back to front of the room, the force is upward, therefore using left hand rule the magnetic field is from right to left.

Conclusion:

Using left hand rule the magnetic field is from right to left.