Calculations for accelerating particles in a Cyclotron

AI Thread Summary
The discussion revolves around calculations for accelerating particles in a cyclotron, specifically addressing discrepancies in kinetic energy results. One participant calculated a kinetic energy of 16.45 MeV, while the expected answer was 165 keV, leading to confusion about the values used, particularly the radius measurement. It was suggested that the official answer might be incorrect due to a potential mix-up between centimeters and millimeters. Additionally, there was a query about explaining part e, with a focus on the effects of electric field strength on particle exit time and kinetic energy. The conversation emphasizes the need for clear expressions and understanding of kinetic energy in relation to the electric field.
sss1
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Homework Statement
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Relevant Equations
mv^2/2, f=qB/2pim
For this question part d, KE=mv^2/2=q^2B^2r^2/2m (I rearranged B=mv/qr for v and subbed into mv^2/2). q^2b^2r^2/2m=2F_cyc^2r^2m(pi)^2
But when I subbed the values in I got 16.45MeV but the answer says 165keV instead. I'm not sure what went wrong?

What's a good explanation for part e also?
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sss1 said:
But when I subbed the values in I got 16.45MeV but the answer says 165keV instead. I'm not sure what went wrong?
I got the same answer as you. (Except I rounded mine to an appropriate number of significant figures!)

It looks like the official answer is wrong - probably because whoever did it used r =53mm instead of r=53cm.

sss1 said:
What's a good explanation for part e also?
As you probably know, ther rules here require you to show your own thoughts/attempt before guidance is offered.
 
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Steve4Physics said:
As you probably know, ther rules here require you to show your own thoughts/attempt before guidance is offered
Well if the e field is strong, it’ll only take a few cycles until the particle leaves? Whereas if if the e field is weak, it’ll take a long time to leave the cyclotron, so the KE is the same regardless?
 
sss1 said:
Well if the e field is strong, it’ll only take a few cycles until the particle leaves? Whereas if if the e field is weak, it’ll take a long time to leave the cyclotron, so the KE is the same regardless?
You need to do better than that. What is an expression for the kinetic energy of the particle just before it exits? Is there an ##E## in it?
 
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