SAT Subject Physics Practice Question 606: Answer and Explanation
Which line shows the path of beta radiation in a magnetic field?
Correct Answer: D
The correct answer is (D). Again, we use the right-hand rule as we did in the previous question. Point your finger toward yourself and your thumb in the direction of motion of the particle. Now is the time you must remember the right-hand rule is used for positive particles. Your palm points down but the electron is negative. It moves in the opposite direction from the proton. This means the electron curves toward Point B, but to reach Point B it must travel in a partially straight pathway. The correct pathway is one where the electron (particle B) curves continuously until it leaves the magnetic field.