http://www.princeton.edu/~jdpeters/docs ... piad99.pdf
I can't understand why the answer is E.
The velocity with which the ion enters the magnetic field is determined by
1/2 m v^2 = q V
ans so v is proportional to sqrt(q/m).
The radius of the arc in a magnetic field of strength B is proportional to (m * v) /q which is proportional to sqrt(m/q).
Since the oxygen is double the charge and quadruple the mass, we expect oxygen to have a radius which is increased by a factor of sqrt(2)
Physics Olympiad 29

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 Joined: Wed Mar 26, 2008 9:14 am
Re: Physics Olympiad 29
yes even i have this same problem.. i think there is a mistake with the answer keynoospace wrote:http://www.princeton.edu/~jdpeters/docs ... piad99.pdf
I can't understand why the answer is E.
The velocity with which the ion enters the magnetic field is determined by
1/2 m v^2 = q V
ans so v is proportional to sqrt(q/m).
The radius of the arc in a magnetic field of strength B is proportional to (m * v) /q which is proportional to sqrt(m/q).
Since the oxygen is double the charge and quadruple the mass, we expect oxygen to have a radius which is increased by a factor of sqrt(2)
Re: Physics Olympiad 29
Okay. That's a relief. I thought I was going crazy.