# Question:Parallel capacitors and electric beams

• Joop!!
In summary, the conversation is discussing the calculation of the angle of deflection for an electron beam passing through a space between two capacitor plates. The force acting on the electron is found by relating the potential difference of the plates to the charge on the plates, and considering the electric field. The magnetic field does not need to be considered in this calculation.

#### Joop!!

An electron beam is send perpendicular onto an electric field between two capacitor plates. The electrons got their kinetic engergi by being accelerated through a potential difference V. The potential difference between the capacitor plates are also V.
The distance between the plates is d, and the length of the plates is a in the direction the electrons move. The electric field is uniform between the plates and 0 outside the plates.The electrons do not hit the plates.

Calculate the angle that the electron beam is deflected by the passage through the space between the plates. How does the angle depend on the potential difference?

This may sound stupid, but i have spend an hour just searching for a formula i could use to solve this problem. I have no idea how to get the angle into a formula.

First i would try to fin the electric field.

So first (Q/V)=e0(A/d) isolate to find Q

and the use F=q(E+VxB)

But I am not really sure if this even makes any sense, can anyone help me get started?

F=q(E+VxB)

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HINT: Can you relate the potential different of the plates to the force acting on the electron?

Okay.

F=qE and Q=CV

gives

F=CVE so that would give me the force that affects the electron beam between the plates. But it still doesn't make much sense, there must also be a magnetic field that i have to consider.

Joop! said:
Okay.

F=qE and Q=CV

gives

F=CVE so that would give me the force that affects the electron beam between the plates. But it still doesn't make much sense, there must also be a magnetic field that i have to consider.
You need to be careful here, Q refers to the charge on the capacitor plates whereas q refers to the charge of the electron. They are two 'unrelated' quantities.

As for the magnetic field, there is no need to consider it here. Yes, the electron produces a magnetic field, but this will not affect the trajectory of the electron since the magnetic field will only affect charges moving relative to the electron.

## What are parallel capacitors and electric beams?

Parallel capacitors and electric beams are two components commonly used in electrical circuits. Parallel capacitors are two or more capacitors connected side by side, allowing the flow of current to split between them. Electric beams, also known as electric fields, are created by charged particles and can be used to transfer energy or information.

## How do parallel capacitors and electric beams affect each other?

In a parallel circuit, the electric beams from each capacitor will interact with each other, resulting in a change in the overall electric field. This change in the electric field can affect the flow of current in the circuit, which in turn can impact the behavior of the parallel capacitors.

## What is the role of parallel capacitors and electric beams in electronic devices?

Parallel capacitors and electric beams are essential components in electronic devices as they can store and transfer electrical energy. Capacitors are used to filter out unwanted signals and stabilize voltage, while electric beams are used to transfer information and activate components in a circuit.

## How are parallel capacitors and electric beams measured and calculated?

The capacitance of parallel capacitors can be calculated by adding the individual capacitance values of each capacitor. The electric field strength of an electric beam can be measured using a voltmeter or by using the mathematical formula for electric field strength, which takes into account the distance between the charged particles and the magnitude of their charges.

## What are some real-life applications of parallel capacitors and electric beams?

Parallel capacitors are commonly used in power supplies, filters, and audio equipment. Electric beams are used in a variety of devices such as antennas, touch screens, and particle accelerators. They are also used in medical imaging technologies, such as MRI machines, to create detailed images of the body.