tag:blogger.com,1999:blog-8705083632203739705.post7207757301355634946..comments2024-01-08T01:42:56.289+05:30Comments on PHYSICS Information and Links: GATE 2012, Question Paper, Download, Answer key, pdf file 12 february - Comment the description of AnswersUnknownnoreply@blogger.comBlogger70125tag:blogger.com,1999:blog-8705083632203739705.post-31954159513560281352015-03-01T20:11:55.768+05:302015-03-01T20:11:55.768+05:30GATE 2012 Answer Key<a href="https://physics43.files.wordpress.com/2015/02/gate-2012-answer-keyph-physicskerala.pdf" rel="nofollow">GATE 2012 Answer Key</a>Shttps://www.blogger.com/profile/08625054792778496944noreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-18683884059578012052012-05-24T16:00:56.896+05:302012-05-24T16:00:56.896+05:30i agree with your commenti agree with your commentAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-53765553131544343782012-03-13T18:59:48.382+05:302012-03-13T18:59:48.382+05:30hiii, arpan. your ans of question 24 is wrong.it w...hiii, arpan. your ans of question 24 is wrong.it wil b (D).As it is unsymmetrical .ground state energy wl b 3/2 hcros omega.so first e.state wl 7/2 hcros omegapravatinoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-16627724116459153902012-03-12T22:15:26.302+05:302012-03-12T22:15:26.302+05:30@Anonymousexplanation of q.no.-35 is---both move i...@<a href="#c3624417688604657701" rel="nofollow">Anonymous</a><br><br>explanation of q.no.-35 is---<br><br>both move in same direction so first find relative velocity i.e-<br> (2c/3)-(c/2)<br> c/6<br>then put this velocity c/6 in length conraction formula you get<br> ans. 35-DAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-23510223062640201722012-03-12T22:09:15.995+05:302012-03-12T22:09:15.995+05:30@DINESH IIT BOMBAYmy dear Dinesh-- Ans. 3-Bplease ...@<a href="#c8215825542802204531" rel="nofollow">DINESH IIT BOMBAY</a><br><br>my dear Dinesh--<br> <br>Ans. 3-B<br><br>please see the below notes of chapter-9 of quantum mechanics by David j Grifith.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-10629300711435435442012-03-12T22:01:48.444+05:302012-03-12T22:01:48.444+05:30@Anonymousexplanation of q. no. 38 is-------you kn...@<a href="#c7866462315374517551" rel="nofollow">Anonymous</a><br><br>explanation of q. no. 38 is-------<br><br><br>you know the partion function given by-: <br> Z=sigma*g*exp(-beta*E(energy))<br>here g is called degeneracy.<br><br>and sigma run from 1 to 3 bcoz three energy levels are given i.e<br>0, e , 2e.so<br><br> Z=1*exp(-beta*0)+2exp(-beta*e)+1*exp(-beta*2e)<br>here 2 is multiplied in second term bcoz in question says that the energy level 'e' are two fold degenerated i.e the degeneracy g=2.<br><br>so- Z=1+2exp(-beta*e)+exp(-beta*2e)<br><br>so- Z=(1+exp(-beta*e))^2<br><br>so answer is-- 38-C.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-91977589860225335492012-03-01T18:37:07.073+05:302012-03-01T18:37:07.073+05:30how acc. To ur own explanatin answr of q 38 is cor...how acc. To ur own explanatin answr of q 38 is corect.its d instead c.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-60777583182054560692012-02-29T12:31:02.405+05:302012-02-29T12:31:02.405+05:30hello .. any idea abt dis years cutoff for ph??hello .. any idea abt dis years cutoff for ph??Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-54403522106455115922012-02-27T07:47:24.494+05:302012-02-27T07:47:24.494+05:30@MOHIT SHARMA IIT@KGPits(40) a standard ques wid s...@<a href="#c7528356305500090724" rel="nofollow">MOHIT SHARMA IIT@KGP</a><br>its(40) a standard ques wid standard fig...nd 1 basic thing prob f electron in nucleus shud b zerojust a humanhttp://www.blogger.com/profile/15647613896819569530noreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-91948446340211744032012-02-24T11:07:24.884+05:302012-02-24T11:07:24.884+05:30Read the end line of question 62.THE probability t...Read the end line of question 62.<br>THE probability that a randomly chosen shock obsorber,which is found to be reliable, is made by Y is.....Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-48875927263048638082012-02-23T20:11:26.077+05:302012-02-23T20:11:26.077+05:30@Anonymous my friend I would like to correct you.....@<a href="#c7696300276361650142" rel="nofollow">Anonymous</a> my friend I would like to correct you...... the question nowhere ask us to pick the shock absorber from the reliable one.... it ask us to pick the shock absorber randomly.... so there is probability of getting non reliable shock absorber also...Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-59222153126670310092012-02-23T10:56:40.627+05:302012-02-23T10:56:40.627+05:30U r right. But .288 represents the shock obsorber...U r right.<br> But .288 represents the shock obsorbers which are reliable. so probability is number of reliable shock obsorbers divide by the total number of reliable cases.<br><br>I think so........Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-7560920306382275732012-02-22T16:00:38.466+05:302012-02-22T16:00:38.466+05:30@Anonymous but according to the question of probab...@<a href="#c787730544763830774" rel="nofollow">Anonymous</a> but according to the question of probability the question ask us to calculate the probability of finding the reliable shock absorber which are made by Y from all (i.e. we have to include the probability of getting non reliable also) so the answer is 0.288Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-45130591461256232762012-02-22T11:11:46.703+05:302012-02-22T11:11:46.703+05:30ans to Q.38 is C because Z = ge^-β€acc. to Questi...ans to Q.38 is C because<br> Z = ge^-β€<br>acc. to Question<br>Z = 1 + 2e^(-β€) + e^(-2β€)<br>where g is the degeneracy factor, <br>can u plz explain me ans to q. 35 and 36Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-10743408757013574732012-02-21T11:55:57.040+05:302012-02-21T11:55:57.040+05:30plz explain the answer to q. no. 38plz explain the answer to q. no. 38Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-28029405791461229612012-02-21T11:51:11.063+05:302012-02-21T11:51:11.063+05:30in question no. 62,suppose total 100 shock obsorbe...in question no. 62,<br>suppose total 100 shock obsorbers company has to buy.then 60 will be supplied by X and 40 by Y.<br>(.40*72)/100=.288<br>(.60*96)/100 =.576<br>then probabilty is .288/(.577+.288) =.334 <br>so, ans is BAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-14080004388228381972012-02-20T11:05:14.867+05:302012-02-20T11:05:14.867+05:30can anyone explain me the question (62) an automob...can anyone explain me the question (62) an automobile plant ........Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-49357272038791070312012-02-20T10:34:53.092+05:302012-02-20T10:34:53.092+05:30HERE 1/2 FACTOR WE ARE GETTING FROM ENERGY DENSITY...HERE 1/2 FACTOR WE ARE GETTING FROM ENERGY DENSITY FORMULA AND WE HAVE TO GET AVERAGE SO 1/2 FACTOR WILL COME OUT FROM AVERAGE OF COSINE SQUARED.DINESH IIT BOMBAYnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-67106252278039554222012-02-20T10:21:11.515+05:302012-02-20T10:21:11.515+05:30for linearly indepdent vectors p*vector a +q*vecto...for linearly indepdent vectors p*vector a +q*vector b =0 where p and q should be zero explicitly.so answer A is correct for question 1.DINESH IIT BOMBAYnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-61125008167543332532012-02-18T15:00:54.899+05:302012-02-18T15:00:54.899+05:30correct answers1-b2-c3-a4-c (2*10/pi)5-d6-a7-b8-d9...correct answers<br>1-b<br>2-c<br>3-a<br>4-c (2*10/pi)<br>5-d<br><br>6-a<br>7-b<br>8-d<br>9-c (elementary particles, all other not)<br>10-doubt<br><br>11-a (use reflectivity equation with n=3/2)<br>12-c (conductivity 0.288, take invesrse)<br>13-a (for 2D kinetic energy Kb T, but here K.E=1/2 mv^2=1/2 m(Vx^2+Vy^2). Since they asked mean (1/2) of velocity square answer is a <br>13-a<br>14-b<br>15-b<br><br>16-c (first raman line 6B)<br>17-b<br>18-b<br>19-d<br>20-doubt<br><br>21-d (properties of nuclear force)<br>22-a<br>23-<br>24-<br>25-c<br><br>26-a<br>27-<br>28-a<br>29-b<br>30-c<br><br>31-d<br>32-a<br>33-c<br>34-d<br>35-b<br><br>36-c<br>37-(a or c)<br>38-c<br>39-b<br>40-d<br><br>41-<br>42-b<br>43-<br>44-d<br>45-d<br>46-<br>47-a<br><br>48-c (free space-V=0)<br>49-d (for real part wave function and its conjugate are same)<br>50-a<br><br>51-b (square \omega and integrate both side from -pi/a to +pi/a)<br>52-<br>53-<br>54-b<br>55-b<br><br>56-<br>57<br>58-b<br>59-q<br>60-b<br><br>61-<br>62-b<br>63-b<br>64-<br>65-aAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-3527886910523676322012-02-18T12:10:17.276+05:302012-02-18T12:10:17.276+05:30@Physics LoverFor 20) answr is A)becoz the voltage...@<a href="#c6652524867225989635" rel="nofollow">Physics Lover</a><br>For 20) answr is A)<br><br>becoz the voltage at the inverting terminal is +1V becoz of the voltage divider connected.<br><br>so as soon as the voltage at the non-inverting terminal(vin) goes above +1V the output will go into positive saturation(+10V)<br><br>So this happens only in option A)Raj Nairhttp://www.blogger.com/profile/08365842282671318583noreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-3272807285184976892012-02-18T12:05:16.634+05:302012-02-18T12:05:16.634+05:30@Physics Loverfirst have a look at this linkhttp:/...@<a href="#c8754723517596270466" rel="nofollow">Physics Lover</a><br><br>first have a look at this link<br><br>http://www.physicsforums.com/showthread.php?t=49807<br><br>Actually P(r) = r^2*Exp[-r] where i have not included the constants<br><br>but the point is that we do have a variable r^2(coming from the volume element) multiplied by the exponential so the function goes to zero as r goes to zero.<br><br>So the answer is D)Raj Nairhttp://www.blogger.com/profile/08365842282671318583noreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-56483566778413520032012-02-18T11:11:23.318+05:302012-02-18T11:11:23.318+05:30@Physics LoverIf u look in griffiths ch 9 eq 9.55 ...@<a href="#c8125924975928517017" rel="nofollow">Physics Lover</a><br><br>If u look in griffiths ch 9 eq 9.55 <br><br>it says that u = epsilon E^2 <br><br>and that the electric and magnetic contributions are equal <br><br>im not sure now but i think vector E is to be substitued in equation 9.55 which is epsilon E^2Raj Nairhttp://www.blogger.com/profile/08365842282671318583noreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-78862832167135215102012-02-17T21:32:11.232+05:302012-02-17T21:32:11.232+05:30Can anybody tell me the answers for 20,33 and 43 w...Can anybody tell me the answers for 20,33 and 43 with explanation?Physics Loverhttp://www.blogger.com/profile/02129107124237812432noreply@blogger.comtag:blogger.com,1999:blog-8705083632203739705.post-1665083938615255562012-02-17T21:30:08.093+05:302012-02-17T21:30:08.093+05:30@Raj NairBut i think in the hyperphysics link,the ...@<a href="#c148622919597025877" rel="nofollow">Raj Nair</a><br><br>But i think in the hyperphysics link,the graph is not similar to ours for it plots the derivative of probability density.<br><br>The probability density is P(r)=1/(4*Pi*a^3)exp[-2r/a0]<br><br>when r/a0=0,<br><br>P(r)=1/4*Pi*a0^3 which is nonzero.<br><br>In the option D, P(r)=0 for r/a0=0<br><br>Also I can't understand how this can be approximated to function of the form x^2 exp[-2x] when a0 is a constant,not variable here.<br><br>Can you pls explain these?Physics Loverhttp://www.blogger.com/profile/02129107124237812432noreply@blogger.com