Direction of electron in magnetic field?

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SUMMARY

The discussion centers on determining the possible directions of an electron moving in a magnetic field. An electron with a speed of 4.00 x 105 m/s experiences an upward magnetic force of 1.00 x 10-14 N in a uniform magnetic field of 3.2 T pointing south. The correct angles, calculated using the formula F = qvBsin(theta), are 182.8 degrees and 357.2 degrees clockwise from south, correcting the initial miscalculations of 267.2 degrees and 92.8 degrees.

PREREQUISITES
  • Understanding of the Lorentz force equation: F = qvBsin(theta)
  • Knowledge of vector components in magnetic fields
  • Familiarity with the left-hand rule for magnetic forces
  • Basic trigonometry for angle calculations
NEXT STEPS
  • Study the application of the Lorentz force in different contexts
  • Learn about the left-hand rule and its implications in electromagnetism
  • Explore the effects of varying magnetic field strengths on charged particles
  • Investigate the behavior of electrons in different types of magnetic fields
USEFUL FOR

Physics students, educators, and anyone studying electromagnetism or the behavior of charged particles in magnetic fields will benefit from this discussion.

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Homework Statement



An electron moves with speed 4.00 105 m/s in a uniform magnetic field of 3.2 T, pointing south. At one instant, the electron experiences an upward magnetic force of 1.00 10-14 N. In what possible directions might the electron be moving at that instant? Give your answers as angles clockwise from south (from 0° to 360°), in increasing degrees.

(I have to find two answers in degrees, both clockwise from south).

Homework Equations



F = qvBsin(theta)

The Attempt at a Solution



F = qvBsin(theta)

sin(theta) = F / qvB

= (1x10-14) / [(1.6x10-19)(4x105)(3.2)]

= .0488

theta = sin-1(.0488)

theta = 2.8

So my first angle was approximately 2.8. I subtracted that from 270 degrees ("south") to get my final angle of 267.2 degrees. Then I subtracted 2.8 from 180 to get my second angle, which was approximately 177.2. I subtracted THAT number from 270 degrees to get my final second angle of approximately 92.8 degrees. I thought that 267.2 and 92.8 were my answers, but they are coming up as incorrect. I also tried rounding to a whole number, which didn't work either.
 
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I wouldn't "subtract from 270".
The 2.8 is already the angle from south.
According to the left hand rule, it has a component to the left, so it must be 2.8 degrees counterclockwise from south. That would 357.2 degrees clockwise from south.
 
It was 182.8 and 357.2. Thanks!
 

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