Force on an electron in magnetic field:

AI Thread Summary
The discussion focuses on calculating the force on an electron moving in a magnetic field using the formula F=q(v X B). The user initially calculated the cross product of the electron's velocity and the magnetic field, resulting in a vector of <1.8e6, 1.2e6, 3.15e6>. After multiplying by the charge of the electron, they obtained a force vector of <28.8, 19.2, 50.4> pN. Another participant pointed out a potential miscalculation in the first component of the force, suggesting it should be 0.28 pN, and emphasized the importance of specifying the answer as a vector rather than just a magnitude. The discussion highlights the need for careful calculations and clarity in presenting results.
krtica
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Q:What is the force on an electron that has a velocity equal to 2e6 m/s i - 3e6 m/s when it is in a region with a magnetic field given by 0.75 T i + 0.45 T j - 0.60 T k?

F=q(v X B)

I took the determinate of the electron's velocity and magnetic field and came up with <1.8e6,1.2e6,3.15e6> then multiplied my answer by 1.6e-19 C. My final answer is <28.8,19.2,50.4>pN.

Did I miscalculate anything?
 
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Assuming the -3e6 m/s speed component is along j, I get same result as you for vXB, but for the force you may want to check the magnitude of you result (I get 0.28 pN for first component). The problem text didn't mention if the result should be specified as a vector or as a magnitude (i.e. |F|), so it would probably be nice touch to include both in your answer.
 
The answer is asked to be given as a vector.
 
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