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?
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Bert, because the charged particle's velocity can have a vertical component only if an electric field in the vertical direction is present.
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Stuart, because a component of velocity in the vertical direction is not changed by a vertical component of a magnetic field.
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Bert, because a component of velocity in the vertical direction is changed by a vertical component of a magnetic field.
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Stuart, because an electric field in the vertical direction would cause the particle to come to a complete stop.
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Neither, because particles cannot move in helical paths in the presence of magnetic and electric fields.
One DNA double helix becomes two
Sergeant Stubby wearing his uniform and medals.
An electric sphygmomanometer.
Electric Charges
The polypeptide II helix
A particle (q = -4.0 mC, m = 5.0 mg) moves in a uniform magnetic field with a velocity having a ...