Photocurrent's dependence on frequency
Photoelectric Effect - Dependence of current on frequency
PHP function substr() error My 3 years old doesn't tell me when he needs to use the bathroom My son is 3 years old and doesn't tell me when he needs to use the bathroom. It has been 5 months now that I took his diaper off him. I just do not know what I should do.  Should I put a diaper on him again?  I mean, is this normal? Please help. I get frustrated sometimes.  He doesn't want to potty at all! I did train him before but now that he understands, he doesn't want to go to potty. Log out button illogical placement In the previous version the logout button is under your username, which it can be found by clicking the down arrow. However, in the new version, after a couple minutes of searching, it is under the "site-switcher" button:        This is really illogical since the logout button is usually under your username, including Google and Yahoo! services.  I suggest bringing back the  which will definitely benefit new users and even old users. Escaped line break tag in tooltip on election page How to view/erase images from both CF and SD cards on Canon EOS 5D mk3? I've been trying to setup my Canon EOS 5D mk3 to shoot in "backup mode". I have two cards:    32GB CF  8GB SD   I've set it like the following:  SET UP1 menu ------------ Record func.:       Rec. separately Playback:           1 [CF]  SHOOT1 menu ------------ Image type/size CF: RAW 22M Image type/size SD: JPEG 9,8M   It works ok, except I have one problem. Since I have only these two cards, on some large shoots I need to erase some in order to free some space to make the card last till the end of shoot.  When viewing images and deleting the ones I want to delete, it seems that I can only see the contents of the CF card, and when I delete an image I delete only the RAW file saved on the CF.  Is there a way to delete the JPEG from the SD card along with it's RAW "parent" on the CF card? On exactly what criteria is the Electorate badge awarded? There is a badge named Electorate which is going to be awarded on "Voted on 600 questions and 25% or more of total votes are on questions". Can somebody explain this to me?  Voted on 600 Question and 25% are on Question? is this  means   Voted on 600 Posts and 25% are on Question  Can't SO place some easy text or Definitions for average users? Running shell command and capturing the output Consider this question on .  I put out a 200 bounty on the question, but did not get an answer from anyone other than myself that worked.    In fact, my answer is also the highest up-voted on it at this point.  I know that allowing OP's to retract a bounty can be a slippery slope; in fact I think that once the bounty is put up it should stay up.  But why not allow the OP to answer their own questions with a bounty and reward it to them if they receive the same up-votes as others?  Yes, I am fully aware that bounties are a risk.  People will use them for numerous reasons such as trying to draw extra attention to their issues.  However, in my specific question, the only valid answer is the one that I gave.  Had it been anyone else's question, I would have received the bounty, but since it was my own I did not. Which homology groups of a closed orientable 6-manifold can be isomorphic to $\mathbb{Z}^3$? List all $i$ for which there is a closed orientable $6$-manifold $M$ with $H_i(M) =\mathbb{Z}\oplus\mathbb{Z}\oplus\mathbb{Z}$.   I am working on an old exam problem and this one stumped me. Progress so far:  I can take $Y=\mathbb{T}^3 \times \mathbb{S}^3$ and get the desired group for $i =1,5,2,4$ I think. But this construction I believe gives $H_3(Y)=\mathbb{Z}^2$. What to do in this case? Is there a way to see my previous performances with respect to winter-bash? May be something like leagues for winter-bash? I understand that hats are different each year, but at least it would be nice to see the number of hats collected. Possible Duplicate:          On  it's a stated fact that if $I$ and $J$ are coprime ideals of a ring $A$, then $I^k$ and $J^\ell$ are also coprime for any integers $k,\ell$.   There's no proof given. Why is this fact true? Write a number with two decimal places SQL Server How do I remove any Ubuntu brand and trademark from my Ubuntu install? I am running Ubuntu 17.10 and I would like to build a completely de-branded ISO of it. This means not just dropping the Ubuntu name from /etc/lsb_release but also deleting references in the text of the installation program, in the "about this computer" screen and so on.  I've already checked other questions but I do not consider them duplicate because:    is very old and it just turned into a bunch of "try this tool" suggestions  is also old and suggests a tool called relinux that hasn't seen updates in years  does mention APT packages (and I know how this works) but not trademarks   Therefore my questions are:   Starting from a stock Ubuntu 17.10 (or an official derivative), how can I remove references to the Ubuntu trademark and logo? What exact packages do I need to uninstall? Are there images I need to replace? Are there files I need to edit other than /etc/lsb_release?   Please note that I am not interested in removing other names such as Firefox. I am only interested in the name of the distro. Someone told me I need a ticket out of Thailand in order to enter.  I am traveling to Thailand, on March 18th. I have a Ticket from Bangkok to Sweden booked for June 4th.   I will be staying in Thailand for 2 weeks when I arrive there, then traveling around Cambodia, Laos and Vietnam until June 4th when I leave.   With that ticket out of Thailand, will I be able to get in and get a (30 day) Visa-On-Arrival (or not because the ticket out is not within the first 30 days). Or do I need to show proof that I am leaving within 2 weeks of being there at first? Linux file access monitoring Is there any way in unix to find out who accessed certain file in last 1 week? It may be user or some script ftp it to some other place. Can I get a list of user name who accessed certain file? How can I find out who is accessing particular file?? What is the purpose of  in Python — especially with respect to when I would want to use it, and when not? Proof that the One-Dimensional Simple Harmonic Oscillator is Non-Degenerate? The standard treatment of the one-dimensional  (SHO) using the raising and lowering operators arrives at the countable basis of eigenstates $\{\vert n \rangle\}_{n = 0}^{\infty}$ each with corresponding eigenvalue $E_n = \omega \left(n + \frac{1}{2}\right)$. Refer to this construction as the abstract solution.  How does the abstract solution also prove uniqueness? Why is there only one unique sequence of countable eigenstates? In particular, can one prove the state $\vert 0\rangle$ is the unique ground state without resorting to coordinate representation? (It would then follow that the set $\{\vert n \rangle\}_{n = 0}^{\infty}$ is also unique.)  The uniqueness condition is obvious if one solves the problem in coordinate representation since then one works in the realm of differential equations where uniqueness theorems abound. Most textbooks ignore this detail (especially since they often solve the problem both in coordinate representation and abstractly), however I have found two exceptions:   Shankar appeals to a theorem which proves one-dimensional systems are non-degenerate, however this is unsatisfactory for two reasons:   Not every one-dimensional system is non-degenerate, however a general result can be proven for a large class of potentials (the SHO potential is in such a class). The proof requires a departure from the abstract solution since it classifies the potentials according to their functional properties.  Griffiths addresses this concern in a footnote stating that the equation $a \vert 0\rangle = 0$ uniquely determines the state $\vert 0\rangle$. Perhaps this follows from the abstract solution, however I do not see how. What is the difference between linear regression and logistic regression? Israel visa stamp issue I am an Indian national living in London. I need to travel to Israel for work. I will need to apply for a visa but I have been told that it will be stamped in my passport. I have read that Israel knows of the problems travellers face in other Arab countries so they issue a paper visa but the embassy in London told me that it will be stamped in. I travel often in Middle East for work and I do not want any issues in the future. Please advise.  Thanks. How can I get admin access to a Mac without knowing the current password?