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Approximation Probability of particle tunnelling

I've done the working for c) but I'm not sure if it's right and could someone direct me to resources regarding secondary reflections. I've done google searches but couldn't find the info.

Screenshot 2016-12-16 20.27.36.png

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Could you post part (a) and (b)?

It seems to relate to (c).
Your (c) approximated transmission coefficient seems to have missing terms. Where did you get it?
Original post by Eimmanuel
Could you post part (a) and (b)?

It seems to relate to (c).
Your (c) approximated transmission coefficient seems to have missing terms. Where did you get it?


Screenshot 2016-12-17 08.41.09.png

Do you need my answers for those questions too?

For c), I got the equation from: http://quantummechanics.ucsd.edu/ph130a/130_notes/node152.html
Original post by Airess3
Screenshot 2016-12-17 08.41.09.png

Do you need my answers for those questions too?

For c), I got the equation from: http://quantummechanics.ucsd.edu/ph130a/130_notes/node152.html


Are you studying quantum mechanics without any reference text or notes from your lecturer? If there are recommended texts from your lecturer, please state it/them.
Original post by Eimmanuel
Are you studying quantum mechanics without any reference text or notes from your lecturer? If there are recommended texts from your lecturer, please state it/them.


I'm using University Physics with Modern Physics 13th edition.
Original post by Airess3
I'm using University Physics with Modern Physics 13th edition.


Then look at the text. Equation 40.42 is what you are looking for (d). Example 40.7 would give you the idea of how to use 40.42.

You should study your text to know and understand the concept before attempting any problems. Worked examples in this text are useful. too.
Original post by Eimmanuel
Then look at the text. Equation 40.42 is what you are looking for (d). Example 40.7 would give you the idea of how to use 40.42.

You should study your text to know and understand the concept before attempting any problems. Worked examples in this text are useful. too.


I looked through the textbook and couldn't find the equation. It doesn't seem to be laid out like that, my textbook's equations are eq. 11,12, 13 etc. Could you tell me what page it is on?
Original post by Airess3
I looked through the textbook and couldn't find the equation. It doesn't seem to be laid out like that, my textbook's equations are eq. 11,12, 13 etc. Could you tell me what page it is on?


I don't think I can tell you which page (the page that has this info is 1348 for the book that I have) as you said the layout is different.
Don't need to tell me you find different info for your text in page 1348 - I will not be surprised.
You can look into the chapter called Quantum Mechanics (name of chapter should not change and content should not change.)
Since you are studying a university course, there is a need that you learn to look for the info independently. It should be pretty obvious in the chapter as long as you know what are you solving.
Original post by Eimmanuel
I don't think I can tell you which page (the page that has this info is 1348 for the book that I have) as you said the layout is different.
Don't need to tell me you find different info for your text in page 1348 - I will not be surprised.
You can look into the chapter called Quantum Mechanics (name of chapter should not change and content should not change.)
Since you are studying a university course, there is a need that you learn to look for the info independently. It should be pretty obvious in the chapter as long as you know what are you solving.

I did this for the working but the lecturer said the last answer should be 0.0393. What did I do wrong? IMG_20170209_200312.jpg
Original post by Airess3
I did this for the working but the lecturer said the last answer should be 0.0393. What did I do wrong? IMG_20170209_200312.jpg


It should be obvious that 1.3 is incorrect..? T cannot be >1

I also suggest you improve how you lay out your working, and when solving problems you should keep it in algebraic form until you have the final answer, then plug in the numbers
Original post by Airess3
I did this for the working but the lecturer said the last answer should be 0.0393. What did I do wrong? IMG_20170209_200312.jpg


I think the answer is 0.0493 instead of 0.0393.

Please learn to use your calculator properly - this is basic skill or university level skill. Check your kappa result again. You can use order of magnitude to check this kind of calculation.

I would suggest you understand what langlitz has commented. It is a fundamental concept.

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