Magnetic force question - should be easy

AI Thread Summary
To find the magnetic force on an electron moving in a magnetic field, the equation F=qvBsin(theta) is used, with values provided for charge, speed, and magnetic field strength. The initial calculation yields a force of 8.0 x 10^-13 N, but confusion arises regarding the direction of the force components. The right-hand rule is applied, leading to a discrepancy in the signs of the components compared to the textbook answer, which states both components are negative. The user also attempts to use the cross product method but encounters different signs for the components. Clarification on the correct application of the right-hand rule and the cross product is sought to resolve the confusion.
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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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