# Electron and parallel plate question >

• HelloMotto
In summary, the given problem involves finding the distance an electron will travel in a cathode ray tube between parallel plates, given its initial velocity and the electric field intensity between the plates. The electron behaves like a projectile and is accelerated downward by the electric field. To solve, one must find the acceleration, time taken for the electron to reach the screen, and distance traveled in the downward direction. The electric field intensity can be calculated using the given units and there is an equation for the force on an electron based on the electric field. It is important to note that the fringing field at the entry and exit of the plates can be ignored for this problem.
HelloMotto
electron and parallel plate question >:(

## Homework Statement

The diagram below shows an electron entering the region between the parallel plates of a cathode ray tube. The electron has an initial velocity of 4.8x10^7 m/s horizontally and enters the exact middle point between the plates. The electric field intensity between the playes is 3.70x10^4 N/C upward. How far below the point midway between the plates will the electron strike the screen at point P?

http://img246.imageshack.us/img246/9690/26772065aj1.jpg
http://g.imageshack.us/img246/26772065aj1.jpg/1/

## Homework Equations

This is my first time trying this and I have no clue how to approach this questions. Could someone direct my in the right way please?

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Electron behaves like a projectile.Since the direction of the electric field is upwards, the horizontal velocity remains the same. Electric field accelerates the electron in the downward direction. Find the acceleration. Range is given. Find the time taken by the electron to reach the screen. Knowing the acceleration and time find the distance traveled by the electron in the down ward direction.

The units of Electric Field are V/m, so that should give you a hint for how to calculate the E-Field between the plates. Then, there is an equation for the force on an electron, based on the E-Field. That (constant) force acts for the whole time the electron is flying between the plates...

BTW, this question presumably tells you to ignore the fringing field at the entry and exit of the plates...

Ack, rl.bhat was too quick for me!

## 1. What is an electron?

An electron is a subatomic particle that carries a negative charge and is a fundamental component of matter. It orbits around the nucleus of an atom and is responsible for chemical reactions and electricity.

## 2. How are electrons produced?

Electrons can be produced through various processes such as radioactive decay, photoelectric effect, or thermal emission. They can also be artificially produced through techniques like electron beams or particle accelerators.

## 3. What is the role of electrons in electricity?

Electrons are responsible for the movement of electrical current. When a potential difference is applied between two points, electrons flow from the negative terminal to the positive terminal, creating an electrical current.

## 4. How do electrons behave in a parallel plate configuration?

In a parallel plate configuration, electrons will experience a force due to the electric field between the plates. They will move from the negative plate towards the positive plate, creating a current.

## 5. How does the distance between the plates affect the movement of electrons?

The distance between the plates affects the strength of the electric field and therefore the force on the electrons. A larger distance results in a weaker electric field and less force, while a smaller distance results in a stronger electric field and more force on the electrons.

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