ToughSTEM
Sign Up
Log In
ToughSTEM
A question answer community on a mission
to share Solutions for all STEM major Problems.
Cant find a problem on ToughSTEM?
0
(a) What is the wavelength of a 7.0-eV photon? (b) What is the de Broglie wavelength of a 7.0-eV electron?
Edit
Added Fri, 07 Aug '15
Community
1
Comment
Add a Comment
Solutions
0
Energy=Plank's constant*c/Wavelength

Energy=7*1.602 E-19 in joules
c=3E8 m/s
h=Plank's constant=6.626 E-34

Now, wavelength=hc/E=1.77 E -7 meters = 177 nm (ultraviolet)

For DeBroglie,

Wavelength=h/momentum=h/mv

at these energies (7ev) we don't need to correct for relativistic mass, so...

momentum=p=mv=square root (2m*Kinetic Energy)

mass=9.109 E -31kg,

so Deb wavelength=4.64 E-10 meters = .464 nm
Edit
Added Fri, 07 Aug '15
Community
1
Comment
Add a Comment
Add Your Solution!
Close

Click here to
Choose An Image
or
Get image from URL
GO
Close
Back
Add Image
Close
What URL would you like to link?
GO
α
β
γ
δ
ϵ
ε
η
ϑ
λ
μ
π
ρ
σ
τ
φ
ψ
ω
Γ
Δ
Θ
Λ
Π
Σ
Φ
Ω
Copied to Clipboard

Add Your Solution
Sign Up
to interact with the community. (That's part of how we ensure only good content gets on ToughSTEM)
OR
OR
ToughSTEM is completely free, and its staying that way. Students pay way too much already.
Almost done!
Please check your email to finish creating your account!
Welcome to the Club!
Choose a new Display Name
Only letters, numbers, spaces, dashes, and underscores, are allowed. Can not be blank.
Great! You're all set, .
A question answer community on a mission
to share Solutions for all STEM major Problems.
Why
The Purpose
How
The Community
Give Feedback
Tell us suggestions, ideas, and any bugs you find. Help make ToughSTEM even better.