What Determines the Speed and Frequency of an Electron in a Magnetic Field?

AI Thread Summary
The discussion revolves around calculating the speed, magnetic field, frequency, and period of an electron with a kinetic energy of 1.92 keV in a magnetic field. The user initially calculated the velocity as 2.85E-23 m/s but found it to be incorrect. Suggestions include re-evaluating the velocity calculation using the provided formula. The conversation emphasizes the importance of correctly applying the equations related to kinetic energy and magnetic forces. Accurate calculations are essential for determining the electron's behavior in the magnetic field.
missyc8
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Homework Statement



An electron with kinetic energy 1.92 keV circles in a plane perpendicular to a uniform magnetic field. The orbit radius is 26.0 cm.
Find the speed of the electron.

Find the magnetic field.

Find the frequency of circling. (Hz)

Find the period of the motion.


Homework Equations


v=sqrt(2*(3.7E-16J/9.109E-31)
k=(mv)^2/2
B-mvqr

The Attempt at a Solution


for velocity i get 2.85E-23 m/s ...but it is wrong...i do not know what to do
 
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missyc8 said:

The Attempt at a Solution


for velocity i get 2.85E-23 m/s ...but it is wrong...i do not know what to do

try computing sqrt(2*(3.7E-16J/9.109E-31)) again
 

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