Why Do Electrons Move in Spiral Trajectories Within a Magnetic Field?

Click For Summary
SUMMARY

The movement of electrons in a magnetic field results in spiral or helical trajectories due to the Lorentz force acting perpendicular to their velocity. This force causes the electrons to orbit magnetic field lines while simultaneously moving along the direction of the field, leading to a downward spiral motion. The Right Hand Rule is essential for determining the direction of this force. Understanding this phenomenon is crucial for students preparing for the SAT Physics Subject Test, particularly those using Kaplan materials.

PREREQUISITES
  • Understanding of the Lorentz force and its application to charged particles
  • Familiarity with the Right Hand Rule for determining force direction
  • Basic knowledge of magnetic fields and their properties
  • Concept of circular motion and its relation to velocity and acceleration
NEXT STEPS
  • Study the Lorentz force and its mathematical formulation
  • Explore the Right Hand Rule in detail with practical examples
  • Investigate the properties of magnetic fields and their effects on charged particles
  • Learn about helical motion and its applications in physics
USEFUL FOR

Students preparing for the SAT Physics Subject Test, educators teaching electromagnetism, and anyone interested in the behavior of charged particles in magnetic fields.

S. Hardt
Messages
6
Reaction score
0
Hello I do not understand one of the problems in my SAT Physics book.

Homework Statement



The subsequent path of the electron is...
.
the answer for this given by the book is : Spiral or Helix
(It does not exist any picture in the book to this question.)

The explanation the book gives for this answer is:
The electron will orbit a magnetic field line but will also continue to move towards the bottom of the page , spiraling downwards.

My question for this is Why is it moving that way? There is no explanation given.This question is out of the SAT Subject Test: Physics from Kaplan.

It would be nice to get an answer soon.
I am studying SAT Physics in a Club, so we all have got the same problem with this.
 
Last edited:
Physics news on Phys.org
Ah okay I figured out half of it... there was a picture...
The force applied on the proton is according to the Right hand rule into the page.

So the question left is only: why does a charged particle moves in a spiral into the page and not in a line (of course not in the beginning but after the direction changed).
 
We figured out the answer so there is no reply needed anymore
 

Similar threads

Why does a diamagnetic rod align perpendicular to a magnetic field?
  • · Replies 8 ·
Replies
8
Views
3K
Why is magnetic field B along a straight wire circular not radial?
  • · Replies 14 ·
Replies
14
Views
3K
Electron in a time variable magnetic field
  • · Replies 5 ·
Replies
5
Views
2K
Find the equation of this magnetic field
  • · Replies 6 ·
Replies
6
Views
2K
Magnetic field due to spiral coil
  • · Replies 22 ·
Replies
22
Views
4K
Electric field in a rotating rod in a magnetic field
  • · Replies 3 ·
Replies
3
Views
2K
Electric and Magnetic field acting on an electron
  • · Replies 25 ·
Replies
25
Views
6K
Understanding work in translation and rotation of a magnetic dipole
  • · Replies 1 ·
Replies
1
Views
2K
The right hand rule in a magnetic field
  • · Replies 2 ·
Replies
2
Views
2K
What is the Correct Way to Calculate Magnetic Force on an Electron or Proton?
  • · Replies 7 ·
Replies
7
Views
2K