# Artificial Magnetic Fields – Electromagnetism (Grade 12) -- CRT e-beam deflection

• randomstu1997
In summary, when a steady beam of electrons moves parallel to a wire carrying current, the B-field created by the wire causes a Lorentz force on the electrons, pushing them away from the wire. This can be understood using the right hand rule and the Lorentz force equation, as described in the conversation.
randomstu1997

## Homework Statement

A cathode-ray tube aims electrons parallel to a nearby wire that carries current in the same direction. What will happen to the cathode rays in terms of deflection?

## The Attempt at a Solution

[/B]The Motor force deflects the cathode rays ?

randomstu1997 said:

## Homework Statement

A cathode-ray tube aims electrons parallel to a nearby wire that carries current in the same direction. What will happen to the cathode rays in terms of deflection?

## The Attempt at a Solution

The Motor force deflects the cathode rays ?
View attachment 76670

Your picture doesn't match the question (coil versus parallel wire). Can you please check that?

Sorry. Then let's say a steady beam of electrons move parallel to the wire carrying current. Then what happens? Thanks

Yeah, that matches your problem statement better. :-)

So what do you think? Think about the right hand rule -- what does the B-field look like around the wire? And again use the right hand rule to figure out the Lorentz force on the e-beam from that B-field. Are you familiar with the vector force equation Lorentz force?

The B-field meets 90 degrees to the electron. I am not familiar with lorentz force.

randomstu1997 said:
The B-field meets 90 degrees to the electron. I am not familiar with lorentz force.

Well, you need to understand the Lorentz force to answer this question. Please re-check your textbook or use a Google or Wikipedia search. Please let us know what you find.

Ok I think I got it. According to wikipedia, there must be an opposite reactive force to the force produced by lorentz equation[PLAIN]http://upload.wikimedia.org/math/1/1/7/117693a4a6d55502f66788d04f156c72.png. This opposite reactive force pushes the electron away. Am I right?

Last edited by a moderator:

## 1. What are artificial magnetic fields and how do they relate to electromagnetism?

Artificial magnetic fields are created by man-made devices, such as electromagnets, and are used to mimic natural magnetic fields. These artificial fields are typically created by passing an electric current through a wire, which creates a magnetic field around the wire. This magnetic field can then interact with other magnetic fields, such as those created by permanent magnets, to produce various effects, including the deflection of electron beams in CRT displays.

## 2. How are artificial magnetic fields used in CRT e-beam deflection?

In CRT displays, artificial magnetic fields are used to control the position of the electron beam, which is responsible for creating the images on the screen. By varying the strength and direction of the magnetic field, the electron beam can be directed to different areas of the screen, creating the desired image.

## 3. What factors affect the strength and direction of artificial magnetic fields?

The strength and direction of artificial magnetic fields can be affected by a number of factors, including the amount of electric current passing through the wire, the length and shape of the wire, and the presence of other magnetic fields in the surrounding environment. These factors can be manipulated to control the behavior of the magnetic field and the resulting electron beam deflection.

## 4. How do artificial magnetic fields impact the overall functioning of a CRT display?

Artificial magnetic fields are essential to the functioning of CRT displays, as they are responsible for controlling the position and movement of the electron beam. Without these fields, the images on the screen would not be able to be created or manipulated, rendering the CRT display useless.

## 5. Are artificial magnetic fields used in any other applications besides CRT displays?

Yes, artificial magnetic fields have a wide range of applications, including in medical imaging, particle accelerators, and magnetic resonance imaging (MRI) machines. They are also used in everyday devices such as speakers, motors, and generators.

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