Exploring Electron Deflection in Oscilloscopes

In summary, the conversation in an electronics class discussed the functioning of an oscilloscope, specifically how the cathode ray tube emits electrons and how they are deflected by electric fields. The question was raised about the absence of an induced magnetic field and it was determined that this is because the professor assumed the electric field to be uniform and not changing with time. If the electric field were changing, it would produce a magnetic field and further deflect the electrons. The Maxwell-Ampère law was also mentioned, stating that the electric field only generates a magnetic field if it is changing with time.
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This was something mentioned in an electronics class today (it's an oscilloscope). I didn't copy it down when I should've, but I was listening rather than scribbling. I hope that I reproduced it properly.

The professor was trying to explain how the cathode ray tube would emit electrons when heated up (which I have represented as a beam for ease of drawing). These would travel through the vertical deflection plates and experience a sideways force due to the electric field. Then they would go through the horizontal plates and be deflected again before being displayed on the screen.

My question is, why is there no induced magnetic field? Is this because the prof was assuming the field between the plates is uniform?

If there was hypothetically a changing electric flux, then there would be an induced magnetic field. My question is, if this were the case, would the electrons experience another force? Would this force deflect the electrons?
 
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Consider the Maxwell–Ampère law [itex] \vec\nabla \times \vec H=\vec J + \frac{\partial \vec D}{\partial t} [/itex] which for your case becomes [itex] \vec\nabla \times \vec H= \frac{\partial \vec D}{\partial t} [/itex]. So the electric field generates a magnetic field, only if its changing with time. So the professor was assuming that the electric field is independent of time.

Yes, if the electric field was changing in time, it would produce a magnetic field and the magnetic field would deflect the electrons further.
 
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What is an oscilloscope?

An oscilloscope is a scientific instrument used to measure and display electronic signals. It works by detecting and amplifying the voltage of an electrical signal and displaying it as a graph on a screen.

How does an oscilloscope deflect electrons?

An oscilloscope uses a cathode ray tube (CRT) to deflect electrons. The electrons are emitted from a heated cathode and then controlled by electric and magnetic fields to create a visual representation of the signal on the screen.

Why is it important to explore electron deflection in oscilloscopes?

Exploring electron deflection in oscilloscopes allows scientists to understand and analyze electronic signals more accurately. It also helps in troubleshooting and diagnosing problems in electronic circuits.

What are the main components of an oscilloscope?

The main components of an oscilloscope include the display screen, the cathode ray tube, the vertical and horizontal deflection plates, the timebase control, and the trigger circuit.

What factors affect electron deflection in oscilloscopes?

The factors that affect electron deflection in oscilloscopes include the voltage and current applied to the deflection plates, the strength of the magnetic field, the speed at which the electrons are accelerated, and the type and amount of material in the CRT.

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