Calculating Energy of Electron with T=0.0017

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The discussion revolves around calculating the energy of an incident electron encountering a potential energy barrier with a height of 5.4 eV and a thickness of 0.73 nm, given a transmission coefficient of 0.0017. Participants emphasize the importance of using the equations for the transmission coefficient and the parameter 'b' to derive the energy. One user expresses frustration over not arriving at the correct answer, initially suggesting a value of 0.203 eV. Others encourage sharing the attempted solution to facilitate guidance and clarify the calculation process. The conversation highlights the complexities of quantum physics and the need for precise calculations in barrier problems.
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Consider a potential energy barrier like that of Fig. 38-15 but whose height U0 is 5.4 eV and whose thickness L is 0.73 nm. What is the energy of an incident electron whose transmission coefficient is 0.0017?

I tried to solve the problem my self but could not get the right answer still having trouble with this question please let me help with this my answer is .203 but not right if some one help me out with this questino and tell me the answer would appreciate that ! thank you very one here are the hint !

The transimission coefficient for a barrier of height U0 and width L is given by
T = e-2bL ...1
Where b = v (8p2m(U0 - E ) / h2 ) ...2
Substituting values in equation (1) we get b
Then substitute b in equation (2) we get E
Givem that U0 = 5.4 eV
m = mass of electron
L = 0.73 nm
T = 0.0017
I hope this may help you.
 
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Quntum physics ! barrier energy !

Consider a potential energy barrier like that of Fig. 38-15 but whose height U0 is 5.4 eV and whose thickness L is 0.73 nm. What is the energy of an incident electron whose transmission coefficient is 0.0017?

I tried to solve the problem my self but could not get the right answer still having trouble with this question please let me help with this my answer is .203 but not right if some one help me out with this questino and tell me the answer would appreciate that ! thank you very one here are the hint !

The transimission coefficient for a barrier of height U0 and width L is given by
T = e-2bL ...1
Where b = v (8p2m(U0 - E ) / h2 ) ...2
Substituting values in equation (1) we get b
Then substitute b in equation (2) we get E
Givem that U0 = 5.4 eV
m = mass of electron
L = 0.73 nm
T = 0.0017
I hope this may help you.
 
What is fig 38-15? =P

and how did you do to get your answer 0.203 ?
 
don;t worry about the figure ? its in the book i cannot tell you the right here but has nothing to do with the answer .. acutally .203 i just plugin the values but i am sure i am not right so please help me out i already set up the equation but still getingg problem to solve this problem !or to find of the energy ..
 
It is straightforward, trivial. You have all values except one right?

Why don't you post your attempt to solution so that we may put you in the right direction instead?
 
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