Determine the radius of the electron's orbit

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pleasez,,,heeeeeelp me

In a simple model of the hydrogen atom, the electron revolves in a circular orbit around the proton with a speed of 2.2*10^6.





Determine the radius of the electron's orbit?
 
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Have you made an attempt? What are your thoughts on the problem?
 


I do not understand the problem
 
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What forces are present in this simple model, and how can you relate them to the circular orbit? (i.e. what is providing the centripetal force?)
 
Read up on anything you might be able to find on http://www.regentsprep.org/Regents/physics/phys06/bcentrif/default.htm.

P.S. To the senior members: was this the right thing to do; provide a link?
 
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V^2/a ?

but l don't have (a) in my problem !
 


afm-91 said:
V^2/a ?

but l don't have (a) in my problem !


Where did v^2/a come from? Did you mean [tex]a_c=\frac{v^2}{r}[/tex]?
 


Ok. Since there is an acceleration, there must be a force, right?

What could possibly be providing this force? In which direction will it act?
 


centripetal force

the direction to the center
 


Yea, there is a centripetal force, but what causes it to exist? For example, a car can travel in a circular path because of the friction between the tires and road surface.
 


What does the nucleus of the atom consist of? How are these sub-atomic particles in the nucleus different to the electron orbiting the nucleus?
 


What does the nucleus of the atom consist of? n+ p

How are these sub-atomic particles in the nucleus different to the electron orbiting the nucleus? ...
 


Yes, there are neutrons and protons in the nucleus. Now, what is the electric charge of each particle? positive/neutral/negative?
 


p >>>>positive

n>>>>>neutral
 


Yep, and the electron is negative.
Ok, so how do electric charges interact? i.e. a positive and a negative electric charge will do what to each other?
 


Correct. Now can you see where the centripetal force is coming from in order to keep the electron in orbit?

Re-answer:
danago said:
Ok. Since there is an acceleration, there must be a force, right?

What could possibly be providing this force? ...
 


Mentallic said:
Yep, and the electron is negative.
Ok, so how do electric charges interact?...
afm-91 said:
Attract each other
Mentallic said:
Correct. Now can you see where the centripetal force is coming from in order to keep the electron in orbit?
afm-91 said:
??/
protons

Err... The answer you've given me is like answering "what keeps the moon orbiting Earth" with "Earth".
But since you've answered the question in parts, yet have been unsuccessful in laying it out into a sentence, then I'll throw it onto a platter for you: "The electrons orbit the nucleus of the atom because of the electrical attraction of the proton and electron due to their opposite charges"

So now we know what is providing the centripetal force (The force that keeps the electron from flying off in a straight line as defined by Newton's first law).

Again, using the equation [tex]a_c=\frac{v^2}{r}[/tex]
where ac= centripetal acceleration
v=velocity
r=radius of orbit

Since you know the velocity, and want to find the radius of the electron's orbit, you'll need to find out what the centripetal acceleration is. Any idea how to obtain that? Hint: Newton's second law.
 
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we can't learn you do this if you don't work hard and try on your own.

I mean, you didn't even know the constituents of the atom, I suggest you study harder in the future so you have at least the background knowledge for the problems you want to solve.