What is the kinetic energy of an electron with a wavelength of 0.850 x 10^-10 m?

AI Thread Summary
To calculate the kinetic energy of an electron with a wavelength of 0.850 x 10^-10 m, the de Broglie wavelength equation is essential. The relevant formula is derived from the relationship between wavelength and momentum, where the momentum p is given by p = h/λ. The kinetic energy can then be calculated using the equation K = p²/2m. The discussion emphasizes the importance of understanding the de Broglie wavelength concept to solve the problem effectively. This approach clarifies the connection between wavelength and kinetic energy for particles like electrons.
Cowtipper
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Homework Statement


If an electron has a measured wavelength of 0.850 x 10^-10 m, what is its kinetic energy?


Homework Equations


I'm not sure.


The Attempt at a Solution


And once again, I'm not too sure. Where do I start?
 
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Find an equation in your textbook that deals with the wavelength of electrons or particles in general. That would be a start.
 
Well, I've got this:

I'm not sure if it's one to use.

E = hc/\lambda

Similarly, I have this one:

K=1/2MV^{2}

However, I'm not sure where or how to use it in this instance, or if I have to use it at all.

Man, this stuff is getting tough. I was doing well there for a while too...
 
Cowtipper said:
Well, I've got this:

I'm not sure if it's one to use.

E = hc/\lambda

No, this equation will not work. Look back in your notes and try to figure out why.

Look up "de Broglie wavelength."
 
hage567 said:
No, this equation will not work. Look back in your notes and try to figure out why.

Look up "de Broglie wavelength."

Aha! That is all I needed to know.

Thanks a lot!
 
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