Particle beams in an electric field

4 minAS Level1.1.21.1.5

AI-drafted, independently checked · not yet teacher-reviewed

By the end of this lesson

By the end you can describe what happens to beams of protons, neutrons and electrons, all at the same velocity, as they pass through an electric field, and explain it using charge and mass.

What you'd see

Fire the three beams, all at the same velocity, between two oppositely charged plates:

Protons (+1) are attracted to the negative plate: a small deflection.
Electrons (−1) are attracted to the positive plate: the opposite direction, and a much bigger deflection.
Neutrons (0) feel no force and go straight through.

Inside the plates each charged beam curves; after the plates it carries on in a straight line.

Quick check

Multiple choiceQuestion 1 · Recall

Beams of protons, neutrons and electrons, all moving at the same velocity, pass between two charged plates. Which describes what happens?

AProtons are deflected more than electrons, because protons are heavier.BElectrons and protons are deflected by the same amount in opposite directions, because their charges are equal and opposite.CAll three beams bend towards the negative plate, the neutrons least.DElectrons are deflected towards the positive plate, by much more than protons are deflected towards the negative plate; neutrons are not deflected.

Answer the question above to continue.

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