Consider the mass spectrometer shown schematically in Figure P19.30. The magnitu
ID: 2026434 • Letter: C
Question
Consider the mass spectrometer shown schematically in Figure P19.30. The magnitude of the electric field between the plates of the velocity selector is 6800 V/m, and the magnetic field in both the velocity selector and the deflection chamber has a magnitude of 0.0570 T. Calculate the radius of the path for a singly charged ion having a mass m = 2.63E-26 kg.
r=?m
Explanation / Answer
We must have during the flat part of the travel that qE = qvB, v = E/B
= (6800 V/m)/(0.057 T) = 119298 m/s
In the deflection chamber, qvB = mv2/r; solving for r, r = mv/qB
= (2.63 * 10-26 kg)(119298 m/s)/(1.602 * 10-19 C)(0.057 T) = 0.344 m