Question

A proton, a deuteron, and an α-particle are accelerated from rest through a potential difference, ∆V = 30 kV. They
enter a region containing a uniform magnetic field of strength B = 0.25 T. The particles move parallel to each other
and perpendicular to B~ .
(a) Compute the kinetic energy of each particle. Which is largest? Which is smallest? By what factor?
(b) Compute the radius of each particle’s cyclotron orbit.
(c) Critical Thinking. Is this setup effective for distinguishing all three particles from each other?
Explain why or why not.

Particle Charge Mass [kg]
proton +1e 1.67 · 10−27
deuteron +1e 3.34 · 10−27
α-particle +2e 6.64 · 10−27

Answer 1