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A cyclotron produces a beam of charged particles useful in medicine. The cyclotron accelerates charged particles in circular path, which allows for longer acceleration path than linear accelerator. A proton is in a cyclotron with an angular momentum of 4e-18 kg m2/s. Its angular speed is 8,000 rad/s. The circular path has a radius of _____ meter.

mass of proton = 1.67 * 10^-27 kg

L = angular momentum
= 4 * 10^-18 = m R^2 omega = 1.67 * 10^-27 * R^2 * 8 * 10^3
R^2 = [ 4/(1.67*8) ] 10^( -18 +27 -3)
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