Bert Says That a Charged Particle in a Vacuum Can

question 50

Multiple Choice

Bert says that a charged particle in a vacuum can travel in a helix only if a uniform electric field and a uniform magnetic field are both present and both parallel to the axis of the helix. Stuart says that only a magnetic field with a component parallel to the axis of the helix is needed. Which one, if either, is correct, and why?

• A) Bert, because the charged particle's velocity can have a vertical component only if an electric field in the vertical direction is present.
• B) Stuart, because a component of velocity in the vertical direction is not changed by a vertical component of a magnetic field.
• C) Bert, because a component of velocity in the vertical direction is changed by a vertical component of a magnetic field.
• D) Stuart, because an electric field in the vertical direction would cause the particle to come to a complete stop.
• E) Neither, because particles cannot move in helical paths in the presence of magnetic and electric fields.

---

Definitions:

Clarification

The process of making a statement or situation less confused and more comprehensible.

Open-ended Questions

Open-ended Questions are inquiries that allow for responses beyond simple yes or no answers, encouraging more detailed and descriptive answers.

Discrepancies

Inconsistencies or differences found between two sets of information, expectations, or outcomes that were supposed to be similar or aligned.

Incongruities

Instances or situations that markedly differ from what is standard, expected, or harmonious, leading to a lack of conformity.