Are electrons constantly orbiting around the nucleus in an atom?

[davon806]

Homework Statement

Hi,I am currently studying A-level physics in the UK.
I have been taught that electrons in an atom are orbiting around the nucleus.
I would like to ask a question:

Consider 2 situations:
(1):
A man is pushing a box forwards along a horizontal road.
Work done = Fs
The chemical energy of the man is converted into the kinetic energy of the box.
(2):
In a closed circuit,chemical energy of the battery is converted to the kinetic energy of
electrons.

That means energy is related to force.Without energy,no force can be exerted on an object.
In my case,if electrons are constantly moving around the nucleus,does it mean that the
nucleus is exerting a force on the electron,so that the electrons have enough energy to
move at any time instant?

If that's true,consider (2) again,the chemical energy in batteries will eventually run out,so that
there will be no more energy supplied to the circuit.
Back to my original concern,once the nucleus has used up its energy,will the electron stop
moving,and stick on the surface of the nucleus?

Thx so much :s

Homework Equations

The Attempt at a Solution

 

[Sunil Simha]

I'll stick to the Bohr's model of the atom here as it makes sense easily. Now if a force is applied on a body, it is not necessary that work is done on it or energy is supplied. Work is defined as F.s or as Fscosθ where θ is the angle between the force and displacement vectors. So if the force is perpendicular to the movement of the object, no work is done on it.

The nucleus of an atom does no work on the electron as it exerts a force perpendicular to the electron's displacement. The electrons are moving because they have energy of their own (kinetic energy).

In case of the electric circuit, the electric field produced by the battery pushes the electrons. Here the battery does work because the force and displacement are parallel. And here the battery also gets exhausted as it uses up its chemical energy to produce a field and push the electrons.

 

[davon806]

I'll stick to the Bohr's model of the atom here as it makes sense easily. Now if a force is applied on a body, it is not necessary that work is done on it or energy is supplied. Work is defined as F.s or as Fscosθ where θ is the angle between the force and displacement vectors. So if the force is perpendicular to the movement of the object, no work is done on it.

The nucleus of an atom does no work on the electron as it exerts a force perpendicular to the electron's displacement. The electrons are moving because they have energy of their own (kinetic energy).

In case of the electric circuit, the electric field produced by the battery pushes the electrons. Here the battery does work because the force and displacement are parallel. And here the battery also gets exhausted as it uses up its chemical energy to produce a field and push the electrons.

Then where does the energy of electron come from?Something must have exerted a force on it so that it can move,do you mean it has kinetic energy intrinsically?

 

[Sunil Simha]

Then where does the energy of electron come from?Something must have exerted a force on it so that it can move,do you mean it has kinetic energy intrinsically?

I guess the electron acquires its kinetic energy when it gets captured by the nucleus. Initially, say the electron was very far away ( you can say that it was in an orbit around the nucleus at infinite distance). Because of the attraction of the nucleus, it was brought into smaller and smaller orbits up to its current position. Here, you can see that the electron lost electrical potential energy and (by energy conservation) gained kinetic energy.

 

[Nickie]

I can provide an explanation for the behavior of electrons in an atom. According to the Bohr model of the atom, electrons do not orbit the nucleus in a circular path like planets orbiting the sun. Instead, they exist in specific energy levels or shells around the nucleus. These energy levels are determined by the amount of energy the electron possesses, and they are not constantly moving around the nucleus.

Electrons do have a certain amount of kinetic energy, which allows them to move within their energy levels. This movement can be described as a wave-like behavior, rather than a circular orbit. The exact location of an electron within its energy level cannot be determined, but rather it exists in a probability cloud around the nucleus.

In a closed circuit, the chemical energy from the battery is converted into electrical energy, which is then used to move the electrons through the circuit. This movement of electrons is not due to a force from the nucleus, but rather from the electrical potential created by the battery.

In terms of your second question, when a battery runs out of energy, it means that all of the chemical reactions that were producing the electrical potential have stopped. This does not necessarily mean that the electrons will stop moving and stick to the nucleus. The electrons will still have their inherent kinetic energy and will continue to move within their energy levels.

I hope this explanation helps to clarify the behavior of electrons in an atom and in a closed circuit. Keep up the good work in your A-level physics studies!