An electron, moving toward the west, enters a uniform magnetic field. Because of this field the electron curves upward. The direction of the magnetic field is

The direction of the magnetic field is towards the North. This can be

determined using the right hand rule by Fleming.

The right hand rule states that to determine the direction of the magnetic

force, the right thumb should be pointed in in the direction of the velocity,

index finger in the direction of the magnetic field and middle finger in the

direction of magnetic force.

When this is applied, we will discover that the index finger will point towards

the north region.

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The magnetic field's direction is towards the north

Explanation:

The force on a positive charge in a uniform magnetic field is represented by the right hand rule. To determine the direction of the force, place your right hand with your palm up, and your thumb at 90° to the other fingers. If the fingers represent the magnetic field, and the thumb the direction of the positive charge, then the palm will push up in the direction of the force. But a negative charge like an electron pushes in exactly the opposite direction. So if you follow this rule, you will find that the magnetic field points towards the north.

a electromagnetic waves

small = small current large mag large current