SAT Subject Physics Practice Question 605: Answer and Explanation
Which line shows the path of alpha radiation in a magnetic field?
Correct Answer: E
The correct answer is (E). Use the right-hand rule to find the direction of the force applied to the alpha particle. The field is oriented out of the page, meaning you point your fingers at yourself and your thumb in the direction of the motion of the particle. Your palm points down toward the letter C, but remember the force exerted on the particle is constant. The pathway will not straighten. The particle continues in a circular path until it exits the magnetic field at E.