# Why does a4n electron need to move in an orbit?

• i82muchpi
In summary: The electric force between the proton and electron is always directed towards the proton, because it has more mass. But the electric force between two particles does not always result in them moving towards each other! In fact, if you have two particles that are constantly exchanging electric force, they will be pushed away from each other.
i82muchpi
Note: This isn't a HW question.

I have learned that the magnitude of charge of a proton and electron is the same (i.e. 1.602 * 10^19 Columbs). Then why does an electron need to move in an orbit because the charges could cancel each other out and the electron could remain stationary.

I realize this might be a newbie question but I was just curious.

Thanks.

i82muchpi said:
Note: This isn't a HW question.

I have learned that the magnitude of charge of a proton and electron is the same (i.e. 1.602 * 10^19 Columbs). Then why does an electron need to move in an orbit because the charges could cancel each other out and the electron could remain stationary.

I realize this might be a newbie question but I was just curious.

Thanks.

It's not a matter of charge "canceling". It's a matter of the existence of an attractive potential. This is similar to the Earth-moon system. Why does the moon needs to orbit the earth? After all, the charges of the Earth-Moon system is already neutral?

Furthermore, the word "orbit" is rather misleading. You might want to read our FAQ in the General Physics forum to realize that this is not your regular classical orbits.

I have no idea what a "4n electron" is in your title. I doubt that you're referring only to the 4n energy state, since that is way too specific.

Zz.

The "a4n" electron is simply a typing mistake. I meant it to be "an electron". Also, sorry about the usage of orbits. I am just used to using the word. I read the General Physics FAQ but I have a few questions.

But I do not still understand why do electrons need to move in the first place? Why can't a stable atom exist with proton and electron both being stationary? What force sets an electron into the moving state in the first place?

i82muchpi said:
The "a4n" electron is simply a typing mistake. I meant it to be "an electron". Also, sorry about the usage of orbits. I am just used to using the word. I read the General Physics FAQ but I have a few questions.

But I do not still understand why do electrons need to move in the first place? Why can't a stable atom exist with proton and electron both being stationary? What force sets an electron into the moving state in the first place?

You mean you cannot reason out why the moon would not stay where it is with respect to the Earth if it isn't orbiting the earth? You do know what a 'central force' is, don't you?

Zz.

No I do not know what a central force is. Kindly explain it for me.

A "central force" is a force whose direction is always towards or away from some central location.

The gravitational force exerted on an object by the Earth is always directed towards the center of the Earth (which we assume to be stationary when the object has much less mass than the earth)

The electrical force that a proton exerts on an electron is always directed towards the proton (which we usually assume to be stationary because the electron's mass is much less than the proton's mass).

i82muchpi said:
But I do not still understand why do electrons need to move in the first place? Why can't a stable atom exist with proton and electron both being stationary? What force sets an electron into the moving state in the first place?

If a proton and an electron are near each other, they can't be stationary, because they attract (+ and - remember?), but since they are each so small, the chances they actually collide is minute. Chances are the electron will miss the proton and settle in an orbital, depending on its initial speed relative to the proton.

I'm not sure if an e- and a proton can actually collide (what about opposing accelerated beams?). Maybe a particle physicist can answer this. If so then an electron would have a cross-section and thus a volume. But I don't think that is the case.

## 1. Why does an electron need to move in an orbit?

Electrons move in an orbit around the nucleus of an atom due to the attractive force between the negatively charged electron and the positively charged nucleus. This force, known as the electrostatic force, keeps the electron in orbit and prevents it from flying off into space.

## 2. How does the electron stay in orbit?

The electron stays in orbit due to its angular momentum, which is the product of its mass, velocity, and distance from the nucleus. This angular momentum creates a centrifugal force that balances the attractive electrostatic force, keeping the electron in orbit.

## 3. What determines the size and shape of an electron's orbit?

The size and shape of an electron's orbit is determined by the energy level it occupies. Higher energy levels are further from the nucleus and have larger orbits, while lower energy levels are closer to the nucleus and have smaller orbits. Additionally, the shape of the orbit is influenced by the number of electrons in the atom and their interactions with each other.

## 4. Can an electron move in any direction within its orbit?

No, an electron can only move in specific orbits around the nucleus, known as energy levels. Within each energy level, the electron can move in any direction, but it cannot move between energy levels without gaining or losing energy.

## 5. Why can't electrons just exist in the same energy level or orbit as the nucleus?

If electrons were to exist in the same energy level as the nucleus, their electrostatic force would cause them to collide and merge with the nucleus. This would disrupt the delicate balance of forces that keep atoms stable and could potentially lead to the breakdown of matter.

Replies
3
Views
1K
Replies
13
Views
4K
Replies
36
Views
4K
Replies
15
Views
3K
Replies
2
Views
1K
Replies
7
Views
2K
Replies
37
Views
5K
Replies
74
Views
13K
Replies
4
Views
6K
Replies
6
Views
1K