Finding Current in a Long Solenoid

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To find the current in a long solenoid with 100 turns/cm, an electron moving at 0.048c in a circular path of radius 2.20 cm is analyzed. The formula used is i = mv/e*mu*n*r, where m is the electron mass, v is speed, e is charge, mu is permeability, n is turns per meter, and r is radius. The initial calculation yielded an incorrect current of 0.266 A, prompting a review of the equation and calculations. After correcting for potential errors, including the need for brackets in the denominator, the correct current was determined to be 0.297 A. Accurate calculations are crucial for solving physics problems involving electromagnetic fields.
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Homework Statement


A long solenoid has 100 turns/cm and carries current i. An electron moves within the solenoid in a circle of radius 2.20 cm perpendicular to the solenoid axis. The speed of the electron is 0.048 c (c = speed of light). Find the current i in the solenoid.



Homework Equations



i= mv/e*mu*n*r

The Attempt at a Solution


i= (9.11E-31kg)(.0480)(3.0E8)/ (1.6E-10 C)(4*pi E-7 Tm/A)(100/.01 m) (2.2E-2) = .266 A
this answer is wrong...
what am i doing wrong? thank you!
 
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Probably a typo but you wrote 1.6E-10 for the charge on the electron.
Of course you need brackets around all the factors in the denominator.
I ran your calc through my calculator and got .297 A.
 
yeah, that's right! i must have messed up on the calculations somewhere!
 

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