Beam Deflection in a Television Tube

AI Thread Summary
The discussion focuses on calculating the deflection of an electron beam in a television tube under the influence of Earth's magnetic field. The beam, with electrons having a kinetic energy of 10.8 keV, deflects eastward due to the vertical component of the magnetic field. The acceleration of a single electron was determined to be approximately 5.95 x 10^14 m/s². To find the deflection distance after traveling 36.0 cm, the time taken to traverse this distance was calculated using kinematic equations. The final displacement was then derived using the previously calculated acceleration and time, leading to a successful resolution of the problem.
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[SOLVED] Beam Deflection in a Television Tube

Homework Statement


Each of the electrons in the beam of a television tube has a kinetic energy of 10.8 keV. The tube is oriented so that the electrons move horizontally from geomagnetic south to geomagnetic north. The vertical component of Earth's magnetic field points down and has a magnitude of 55.0 µT.

How far will the beam deflect in moving 36.0 cm through the television tube?

Homework Equations



F=Bqv
F=ma
K=.5mv^2

d=vi*t + .5at^2 ?


The Attempt at a Solution



I've already completed the first two parts of the problem:
(a) In what direction will the beam deflect? East
(b) What is the acceleration of a single electron due to the magnetic field? 5.949657e14 m/s^2

I'm honestly not sure how to calculate the deflection...do I use kinematic equations? Thanks for any tips you can provide!
 
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Figure out the time it takes to reach the end of the tube, and using this time and your acceleration that you calculated, you can find the deflection using kinematics.
 
Doh! I knew I was overlooking something small. Had to use k=.5mv^2 for the first part to determine the velocity then plug the velocity and displacement into find the time. Once I found the time, I used the acceleration calculated earlier and found the displacement. Simple! Thanks!
 
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