Magnetic Force
You may recall the last programming exercise that involved a particle being accelerated through two charged plates. In this exercise we will add a magnetic field to the right hand side of the simulation. The particle only experiences this field when it passes into the right-hand side. This example is loosely based on the idea of a “mass spectrometer”. It turns out that if you vaporize a little bit of a sample with some unknown molecules there tends to be alot of molecules that lose ONE electron. Since the molecule has lost an electron it has a +1 charge. The mass of the molecule is essentially the same even if it is missing an electron because electrons make up a very, very small fraction of the mass of atoms. As you will learn about in this lab, the trajectory of the particle in the magnetic field tells us something about the mass of the particle (if you already know q, v, and B for example).
Links to Activity
Learning Objectives
At the end of this lesson students will…
- Apply the magnetic force relationship with Newton’s 2nd law to code the trajectory of a moving, positive particle in a magnetic field
- Understand how changes in charge, mass, and magnetic field direction affect the trajectory of the particle.