Particle Accelerators: a Cyclotron of Radius 0

Multiple Choice

Particle accelerators: A cyclotron of radius 0.25 m accelerates nonrelativistic protons in a 1.7-T magnetic field. What is the kinetic energy of the protons when they leave the cyclotron? (1 eV = 1.60 × 10^-19 J, e = 1.60 × 10^-19 C, m_proton = 1.67 × 10^-27 kg)

A) 3.7 MeV
B) 7.8 keV
C) 8.7 keV
D) 7.8 MeV
E) 8.7 MeV