Magnetic force question - should be easy

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SUMMARY

The discussion revolves around calculating the magnetic force on an electron moving in a magnetic field of 0.50 T with a velocity of 1.0 x 107 m/s at a 45-degree angle above the positive y-axis. The magnetic force is computed using the formula F = qvBsin(θ), resulting in a force of 8.0 x 10-13 N. The user encounters confusion regarding the direction of the force components, particularly when applying the right-hand rule and cross product methods, leading to discrepancies with textbook answers.

PREREQUISITES
  • Understanding of the Lorentz force equation: F = qvBsin(θ)
  • Familiarity with vector components in three-dimensional space
  • Knowledge of the right-hand rule for determining force direction
  • Basic proficiency in performing vector cross products
NEXT STEPS
  • Review the application of the right-hand rule in electromagnetic contexts
  • Study the vector cross product in detail, particularly in physics
  • Explore the implications of charge sign (positive vs. negative) on force direction
  • Learn about the behavior of charged particles in magnetic fields
USEFUL FOR

This discussion is beneficial for physics students, educators, and anyone interested in understanding the dynamics of charged particles in magnetic fields, particularly in the context of electromagnetism and vector analysis.

bcjochim07
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Homework Statement



1) An electron moves in a magnetic field B = .50 i with a speed of 1.0 x 10^7 m/s 45 degrees above the positive y axis. What is the magnetic force on the electron?


Homework Equations





The Attempt at a Solution


1)This should be an easy question, but I am getting my signs messed up.

F=qvBsin(theta) q = 1.60*10^-6 v= 1.0 * 10^7 m/s B = .50 T
F= (1.60*10^-6)(1.0*10^7)(.50) = 8.0 *10 ^ -13 +

Now, using the right hand rule I believe that if this were a proton, the components would be
(-5.66*10-13)i + (5.66*10-13)k and so then I just flipped the signs:

(5.66*10-13)i - (5.66*10-13)k , but my book says they are both negative.

Please help, I am confused by this. Is there a better way to think about this?
 
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any thoughts would be greatly appreciated
 
I have also tried doing the cross product between v and B and then multiplying by 1.60 * 10 -19 but then I come up with a positive z component and a negative j component
 

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