Circular Motion with a hydrogen atom

AI Thread Summary
In the discussion about calculating the central force acting on an electron in a hydrogen atom, the user attempts to apply the formula Fc = m*v^2/R using a mass of 1.674e-27 kg and a speed of 2.01e6 m/s. However, they repeatedly receive an incorrect answer from their homework service, UTexas. Other participants point out that the user is likely using the wrong mass value and suggest verifying that it corresponds to the mass of an electron. The correct mass of an electron is approximately 9.11e-31 kg, which should be used in the calculation. Accurate values are crucial for obtaining the correct force in such physics problems.
all_relative
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Homework Statement


In the Bohr model of the hydrogen atom, the speed of the electron is approximately 2.01e6 m/s.
Find the central force acting on the electron as it revolves in a circular orbit of radius 4.84e-11 m.
Answer in units of N.


Homework Equations



Fc=m*v^2/R

The Attempt at a Solution


I said that the mass was 1.674e-27 kg. If i should use another number, please let me know.

Fc=m*v^2/R
Fc=(1.674e-27)*(2.01e6)^2/(4.84e-11)
Fc=1.39e-4

When I submit this answer to UTexas (an online HW service) it says that I am wrong. I have done this problem several times and keep getting the same thing.

Thanks!
 
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all_relative said:

Homework Statement


In the Bohr model of the hydrogen atom, the speed of the electron is approximately 2.01e6 m/s.
Find the central force acting on the electron as it revolves in a circular orbit of radius 4.84e-11 m.
Answer in units of N.


Homework Equations



Fc=m*v^2/R

The Attempt at a Solution


I said that the mass was 1.674e-27 kg. If i should use another number, please let me know.

Fc=m*v^2/R
Fc=(1.674e-27)*(2.01e6)^2/(4.84e-11)
Fc=1.39e-4

When I submit this answer to UTexas (an online HW service) it says that I am wrong. I have done this problem several times and keep getting the same thing.

Thanks!

You are not using the right value for the mass.
 
hage567 said:
You are not using the right value for the mass.

What is the correct value for the mass?
I looked it up on Google and that is what I found.

Thanks.
 
You are looking for the mass of an electron. Is that what you googled?
 

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