Magnetic field on a proton due to an electron

AI Thread Summary
The discussion revolves around calculating the magnetic field produced by an electron orbiting a proton in the Bohr model of the hydrogen atom. The user initially computes the magnetic field using Ampere's law but receives a different result than expected. They realize that using the Biot-Savart law may be more appropriate for this scenario. The confusion arises from the interpretation of the path length, with clarification needed on why it should be considered as 2r. Ultimately, the conversation highlights the importance of selecting the correct approach for such calculations.
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Homework Statement


In Niels Bohr's 1913 model of the hydrogen atom, an electron circles the proton at a distance of 5.29 E-11 m with a speed of 2.19E6 m/s. Compute the magnitude of the magnetic field this motion produces at the location of the proton.

Homework Equations


∫B.ds = μI

The Attempt at a Solution


I found the time it takes the electron to circle the proton,
then the current(I)
by dividing the Q(electron)/time

then i take ds to be 2∏r and B to be constant for the integral..

I got 3.99T, the solution gets 12.5T and uses 2r for the vector ds around the path.
Not sure how the path can be 2r?

Homework Statement


Homework Equations


The Attempt at a Solution

 
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Ampere's law doesn't seem appropriate. Consider Biot-Savart instead.
 
Ahhh i see, yes thankyou
 
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