Modern Physics - Length of infinite well that has an electron

AI Thread Summary
The discussion revolves around solving a physics problem regarding the energy levels of an electron in a one-dimensional infinite potential well. The user is seeking help with calculations from the book "Modern Physics for Scientists and Engineers" by John C. Morrison. They correctly identify the energy formula but make an error in their calculations, specifically missing a square on the Planck constant (h). This oversight leads to an incorrect result for the size of the well, which is calculated to be excessively large at 7.534 x 10^8 m. Correcting the formula will yield a more accurate size for the region.
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Homework Statement


** My book doesn't have any solutions in the back , and I trying to find out if I am doing the problems correctly. My book is Modern Physics for Scientists and Engineers by John C. Morrison. If you know anywhere I can find the Answers. I would greatly appreciate it!

The lowest energy level of an electron confined to a one-dimensional region is 1.0 eV. (a) By describing the electron as a particle in an infinite well, find the size of the region.


Homework Equations



Energy levels of particle in an infinite well:
E=\frac{n^{2}*h^{2}}{8mL^{2}}

The Attempt at a Solution


Formula:
E=\frac{n^{2}*h^{2}}{8mL^{2}}

Variables:
E= 1.0 eV = 1.602e-19 J
n =1
h = 6.626e-34 J*s
m= 9.109e-31 kg
L = ?

1.602*10^{-19}J=\frac{(1)^{2}*(6.626*10^{-34}J*s)}{8*(9.109*10^{-31}kg)*(L)^{2}}

L = 7.534*10^{8}m
 
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