I would say it is NOT a duplicate of this question:  .   While I was studying Faraday's law of classical electromagnetism, I came across this picture:   It is called Faraday's disk and it works as a DC dynamo on a constant magnetic field. However, when I tried to apply Faraday's law I failed: $$ \epsilon = - \frac{d\phi_B}{dt} $$ If both the area of the circuit and the magnetic field are constant (even their direction), I would expect the flux to be also constant. Furthermore, knowing the flux is constant its derivative to time must be zero, so there shouldn't be any inducted electromotive force. It turns out there is.  This is called the Faraday Paradox and it even has its own  article and it is also mentioned here: .  Moreover, the second article (which gives a mathematical proof of the Law from Maxwell Equations) claims that Faraday's Law is not universally applicable and also that Faraday's Disk is a nice counterexample. Is this statement true?   If so, when can this Law be applied and why (mathematical explanations are also welcome)?  If it is an universal law, how can this case be explained?
I have studied that  and motional emf are two different lines of thinking but are essentially same. But then, how can Faraday's paradox be explained by Faraday's law of induction? Particularly in paradoxes in which Faraday's law of induction predicts zero EMF but there is a non-zero . The wikipedia article is more confusing rather than enlightening.  I need an explanation regarding  EDIT : I wanted to know how is flux changing if faraday's law is valid .
I was reading . They are performing a logistic regression (with R). At some point they calculate the probability of getting a residual deviance higher than the one they got on a $\chi^2$ distribution with degrees of freedom equal to the degrees of freedom of the model. Copying-pasting from their website...   &gt; glm( cbind(using,notUsing) ~ age + hiEduc + noMore, family=binomial)  Call:  glm(formula = cbind(using, notUsing) ~ age + hiEduc + noMore,            family = binomial)   Coefficients: (Intercept)     age25-29     age30-39     age40-49       hiEduc       noMore       -1.9662       0.3894       0.9086       1.1892       0.3250       0.8330    Degrees of Freedom: 15 Total (i.e. Null);  10 Residual Null Deviance:      165.8  Residual Deviance: 29.92        AIC: 113.4        The residual deviance of 29.92 on 10 d.f. is highly significant:  &gt; 1-pchisq(29.92,10) [1] 0.0008828339       so we need a better model     Why does it make sense to compute 1-pchisq(29.92,10) and why does a low probability indicate that something is going wrong with their model? I have a netbook that I want to install Ubuntu onto. I do have a good Mac computer that I can make a bootable USB drive from, but I'm confused on how to go about making it. The kernel and range of the powers of a self-adjoint operator How do you get git to always pull from a specific branch? jQuery select and wrap textNode SSH connection problem with "Host key verification failed..." error I can connect to another Ubuntu machine in my LAN via SSH. On both of then PC's I installed   but from another Ubuntu computer I can not connect to my PC via SSH and I got this error:     Host key verification failed... Does flying to Panama from the US reset the ESTA time counter? Algorithm for minimization of sum of squares in regression packages chpasswd apply changes in the chroot directory SQL-Server: The backup set holds a backup of a database other than the existing After the death of Lord Voldemort, Harry was taken to the Dursleys and became known as "The Boy Who Lived".  We know that the Wizarding World found out  that Voldemort was dead and undoubtedly it was Dumbledore that advised people that Harry had somehow survived the attack and caused Voldemort's death. According to Snape (in HP:HBP) there were even persistent rumours that Harry was a powerful Dark Wizard in the making until he turned up at Hogwarts a decade later.  My question is : Where did the Wizarding World think Harry was for the intervening 10 years? A customer of mine wants to pay me from the usa to my account with N26 bank.N26 Bank is a German online bank with no branches but available to customers in the euro-zone.I opened my account online in Portugal.When my customer made the transfer and sent me the slip,i discovered the beneficiary name was completely wrong but the Iban and Swift was correct.Will the wire transfer go through with correct Iban and Swift but incorrect beneficiary name? 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I have two different separate vhosts in /etc/nginx/sites-enabled/,   domain1.org (no HTTPS)  server {      listen                      80;     server_name                 www.domain1.org domain1.org;     root                        /var/www/domain1.org;     index                       index.html index.php index.htm;      error_log                   /var/www/logs/domain1.errors.log;      [ ... ]   domain2.com (with HTTPS)  server {      listen                      443 ssl;     server_name                 domain2.com www.domain2.com;      # INCLUDE SSL CERTIFICATE     include                     sites-enabled/domain2_ssl_include;       root                        /home/domain2/www/www;     index                       index.html index.php index.htm;      [ ... ]   I've included a listener to the port 443 for domain1.org, but once I do that, I get an aborted error from Firefox saying (when accessing ):     This Connection is Untrusted      You have asked Firefox to connect securely to domain1.org, but we can't confirm that your connection is secure.   I opened the technical data, it appears that the domain1.org is using the domain2.com SSL certificate:     domain1.org uses an invalid security certificate.      The certificate is only valid for the following names:    *.domain2.com , domain2.com        (Error code: ssl_error_bad_cert_domain)   So I added this to domain1.org vhost configuration:  server {      server_name                 domain1.org www.domain1.org;      listen                      443 ssl;      rewrite ^ http://domain1.org permanent; }   Which still gets me prompted with the Firefox error.  Now... when I access to , I get an 400 error from nginx saying this:     400 Bad Request      The plain HTTP request was sent to HTTPS port   I am not entirely sure what to do, disabling the https with ssl off; has no effect. How can I actually disable HTTPS for domain1.org but not for domain2.com?  I am using Ubuntu 12.04 running nginx 1.2.6. How to make an international emergency call? CSS3's border-radius property and border-collapse:collapse don't mix. How can I use border-radius to create a collapsed table with rounded corners? This is my attempt to prove that, if $a &gt; 0$, then $\frac{1}{a} &gt; 0$, using just field and order axioms.  $$a &gt; 0 \implies a \cdot \left(\frac{1}{a}\right)^2 &gt; 0 \cdot \left(\frac{1}{a}\right)^2 \implies a \cdot \left(\frac{1}{a}\right)^2 &gt; 0 \implies a \cdot \left(\left(\frac{1}{a}\right) \cdot \left(\frac{1}{a}\right)\right) &gt; 0$$  By associativity of multiplication:  $$\left(a \cdot \left(\frac{1}{a}\right)\right) \cdot \left(\frac{1}{a}\right) &gt; 0$$  We know that $a \cdot \left(\frac{1}{a}\right) = 1$, because one is the multiplication inverse of the other.   So we have:  $$1 \cdot \left(\frac{1}{a}\right) &gt; 0 \implies \frac{1}{a} &gt; 0 $$  Which is what we wanted to prove.   My question are:    In the field axioms, there's no axiom that says that $0$ times another number is $0$, but I have used this property. 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The firmware can be loaded from removable media, such as a USB stick or floppy. The missing firmware files are: iwlwifi-7265-9.ucode iwlwifi-7265-8.ucode If you have media available now, insert it, and continue. Load missing firmware from removable media?  I found the appropriate firmware on Debian website, downloaded it (zip), extracted to flash drive, and booted with flash drive plugged in. I still get the error message that appropriate firmware could not be found (the error message disappear to fast to copy down). How do I properly format the flash drive? Or is the problem here something else? Windows Explorer on another computer tells me the flash drive is 14.6GB and formatted as FAT32. How does RAID 1 determine which drive should act as the source for a rebuild? Here's my scenario -- both drives were working perfectly fine. I removed one of the drives for a while (building a new PC, didn't think I was going to use RAID anymore but changed my mind). I actually switch the SATA type to AHCI and was operating for about a week on the new system before deciding to re-enable RAID and reinstall the drive I had removed.   It's currently rebuilding, but I'm curious how it knows which one is the source and which one is out-of-date? In my online brokerage account, I want to buy a particular stock and I see the following:  Bid:  13.20 x200           Ask:  13.27 x1,000   the current stock price is 13.22.   Can someone explain what the bid and ask prices mean relative to the current price?  If I buy 1000 shares, why would I pay more?