A common way to focus a beam of charged particles is to use an electric field and a magnetic field together. Based on the orientation of the two fields, you can tune the Coulomb and Lorentz forces to direct the beam of particles. This technique spectrometers and scanning electron microscopes. You want to focus a beam of positively charged particles moving in the -z direction. The particles have a mass of 3.30e-2 0.341 T magnetic field in the +x direction. What direction do the particles feel the Lorentz force from the magnetic field?

A common way to focus a beam of charged particles is to use an electric field and a magnetic field together. Based on the orientation of the two fields, you can tune the Coulomb and Lorentz forces to direct the beam of particles. This technique spectrometers and scanning electron microscopes. You want to focus a beam of positively charged particles moving in the -z direction. The particles have a mass of 3.30e-2 0.341 T magnetic field in the +x direction. What direction do the particles feel the Lorentz force from the magnetic field?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter30: Magnetic Fields And Forces

Section30.8: Magnetic Force On A Charged Particle

Problem 30.4CE: Cosmic rays are high-energy charged particles produced by astronomical objects. Many of the cosmic...

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The magnetic field in a cyclotron is 1.25 T, and the maximum orbital radius of the circulating protons is 0.40 m. (a) What is the kinetic energy of the protons when they are ejected from the cyclotron? (b) What Is this energy in MeV? (c) Through what potential difference would a proton have to be accelerated to acquire this kinetic energy? (d) What is the period of tire voltage source used to accelerate the piotons? (e) Repeat tire calculations for alpha-particles.
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A uniform magnetic Held of magnitude 0.150 T is directed along the positive x axis. A positron moving at a speed of 5.00 106 m/s enters the Held along a direction that makes an angle of = 85.0 with the x axis (Fig. P29.73). The motion of the particle is expected to be a helix as described in Section 29.2. Calculate (a) the pitch p and (b) the radius r of the trajectory as defined in Figure P29.73.
Check Your Understanding A cyclotron is to be designed to accelerate protons to kinetic energies of 20 Mev using a magnetic field of 2.0 T. What is the required radius of the cyclotron?
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