Converting Units in the Lorentz Force Law

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The discussion revolves around solving a physics homework problem related to the Lorentz force law, specifically converting the units of the expression 2πm/qB to seconds. Participants suggest starting by identifying the units for mass (m), charge (q), and magnetic field (B), noting that B is measured in Teslas. They recommend using the Lorentz force law, F = q(E + v x B), to relate the units of force to help derive the necessary time unit. The conversation emphasizes understanding the dimensional analysis of the equation to confirm that the units indeed equate to seconds. Ultimately, the focus is on clarifying the relationships between the physical quantities involved.
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Homework Statement



Hello, i am in physics 30 and my teacher gave our class a worksheet for homework and I am stuck on the last question. Could anyone help me out please? Thanks.

Here is the question: Show that the units of 2\pim/ qB are equivalent to seconds.


How can I get the unit for time (s) from that? what do I have to show?


Homework Equations





The Attempt at a Solution



I tried using Fc = Fm but I don't get how 2\pi is used in the equation? Or does it even have an effect and is there just as a constant with no units.
 
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Welcome dulask :smile: Start by writing out all of the units for each symbol in the expression
\frac{2\pi m}{qB}

I do not know what any of them are just by looking at them. I could venture a guess, but I rather not :wink:
 
This problem is kinda annoying as B is in Tesla, q is a charge, m is a mass right? Well here's a nice little trick:

Do you know the Lorentz force law? F = q(E + v x B)? On one side is a force, something with units you should know and are far more comfortable with. On the other side, it has these crazy coulomb and tesla units! I'll assume you may not have gone over it but basically, dimensionally F = qvB! From there you should be able to figure it out.
 
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