Author Question: A velocity selector uses a fixed electric field of magnitude E and the magnetic field is varied to ... (Read 102 times)

2125004343 · **on:** Jul 28, 2018

A velocity selector uses a fixed electric field of magnitude E and the magnetic field is varied to select particles of various energies. If a magnetic field of magnitude B is used to select a particle of a certain energy and mass, what magnitude of magnetic field is needed to select a particle of equal mass but twice the energy?
a. 0.50 B
b. 1.4 B
c. 2.0 B
d. 0.71 B
e. 1.7 B

Question 2

What value of B should be used in a velocity selector to separate out 2.0-keV protons if E is fixed at 80 kV/m?
a. 0.18 T
b. 0.11 T
c. 0.15 T
d. 0.13 T
e. 0.23 T