Electromagnetic field on molecule

[fysik]

hello!

it is known that static electrical field can change the direction of movement of water dripping, etc

I suppose this can also happen with other molecules that are dipoles or somehow influenced by electrical or magnetic field

my question is what are the equation(s) that describe this influence

specifically how the strength of electrical/magnetic field can accelerate at which acceleration an amount of water eg a molecule of water, etc

I need to know what acceleration I can achieve by exposing a molecule of water to an electrical/magnetic field

thanks!

 

[Chandra Prayaga]

If the electric field is uniform, there is no net force on the dipole. The opposite forces on the positive and negative charge of the dipole cancel out, and the molecule as a whole does not accelerate. The molecule just rotates because of the electric field. If the field is not uniform, then the forces on the positive and negative charges are not equal, and then the molecule has a net force on it, and it accelerates. The force, and therefore the acceleration, depends on how non-uniform the electric field is. The force is expressed in terms of the dipole moment and the gradient of the electric field.
In the standard experiment of the change in direction of dripping water, the electric field is non-uniform

 

[fysik]

how much electricity do I need to create a mass spectrometer, that accelerates ions?
does it accelerate ions in vacuum or air?
how fast does it accelerate ions?

 

[nasu]

What do you think? What will be the problem if you try it in air?

 

[fysik]

I think there will be collisions, but maybe the strength of the field will be adequate to maintain a fairly straight acceleration

 

[fysik]

how much electricity do I need to create a magnetic field of 0.01–0.015 T

 

[nasu]

I think there will be collisions, but maybe the strength of the field will be adequate to maintain a fairly straight acceleration

Every collision will change the direction of the ion's velocity. You cannot have a straight trajectory in a gas at normal pressure.
Is this for a school project? I hope you don't really think of building an accelerator.

In what units would you want the amount of "electricity" for your second question?

 

[fysik]

yes, I am thinking to build an accelerator, why?
how did MIT build a handheld mass spectrometer? doesn't this include an accelerator?
any units would be fine

 

[nasu]

Your questions leave the impression that you are not yet understanding the basic principles for such a task.
The people at MIT were a little more advanced when they started the actual construction.
I am sure they knew how to find the "amount of electricity" they will need.

Not that is anything wrong in asking questions, don't get me wrong. :)