Robert Cruikshank
Robert Cruikshank
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Відео

How Beta is Conjugate to Binomial
Переглядів 694Рік тому
A derivation of the relationship between prior beta distribution, binomial data, and an updated beta distribution.
The Beta Function: Solving the Defining Integral for integer a,b
Переглядів 283Рік тому
The Beta Function (as opposed to the Beta Distribution) is defined both by an integral and as a combination of gamma functions. I show the two are the same for the case of integer inputs. Wikipedia has more general proofs but I thought this case has more straightforward calculus.
CDFs for Exponential Rayleigh Weibull and Pareto Distributions
Переглядів 567Рік тому
(revised) I show a pattern in the formulas for a few different probability distributions. These formulas are often scattered in a textbook so I brought them together.
Low Pass, High Pass, or Bandpass Filter?
Переглядів 3,2 тис.Рік тому
Almost zero math. Mnemonic and explanation for several simple cases of filter networks. This is for grasping the concept.
Counting Radial and Angular Nodes in Atomic Orbitals
Переглядів 1,3 тис.Рік тому
A Two Minute Video with the rules and four worked examples.
From Complex Roots to Real Solutions
Переглядів 118Рік тому
Here's a detail that often gets covered quickly in differential equations class. Apologies for the blurriness, I seem to be cursed when it comes to camera technology.
Electric power: Definitions (A Two Minute Video)
Переглядів 139Рік тому
Definitions of power, current and voltage, with brief examples. Made for a viewer by request!
What is E[E[X|Y]] ?
Переглядів 301Рік тому
I work a tiny example with numbers and give a symbolic proof at the end. Hopefully this reduces confusion!
Adding Vectors: TLDW Version
Переглядів 702 роки тому
Here's the 2.5 minute version of the 16.5 minute video I just posted: ua-cam.com/video/bKfto0MKFrg/v-deo.html Season to taste! #physicstutor #physics #tutoringservices #vectors
Adding Vectors: Every. Single. Step.
Переглядів 1202 роки тому
This video is long; it assumes very little knowledge, and is meant for students facing most of the ideas for the first time. I have created a TL;DW version that zips through the same thing at 5x speed. ua-cam.com/video/5Y79FUVpgUU/v-deo.html I hope this helps to save students struggling with the beginning of #physics class! #physicstutor #vectors #tutoringservices
A Tricky F = ma Problem from Kleppner and Kolenkow 1st ed
Переглядів 8322 роки тому
I solve problem 2.19 from K and K in the first 2:30, then problem 2.20 in the rest of the video. linktr.ee/knowledgeoncall robertthetutor.online
Holder Inequality Lemma: A 2 minute proof
Переглядів 7042 роки тому
The Cauchy -Schwarz Inequality is widely used; it turns out to be a special case of the Holder Inequality. That in turn depends on this little lemma, which can be proven with a bit of calculus. The proof is mostly taken from Casella and Berger.
Power and Intensity (an example with sound energy)
Переглядів 1632 роки тому
I work an example of a speaker emitting sound, and talk about the energy, power, intensity, and sound intensity level (dB). This is another video made with slides and a VoiceOver. These certainly upload faster! I'm still getting the hang of making a voice over, so I didn't fight to trim this one down to two minutes flat.
How Voting Works
Переглядів 622 роки тому
Just spelling out things that everybody should already know. Elections are much, much easier than civil war.
Why Study Cyclohexane?
Переглядів 812 роки тому
Why Study Cyclohexane?
Harmonics vs Overtones
Переглядів 2,7 тис.2 роки тому
Harmonics vs Overtones
Why does the Fourier Trick Work? Using trig not integration by parts
Переглядів 9522 роки тому
Why does the Fourier Trick Work? Using trig not integration by parts
Moment and Shear All Along a Cantilever
Переглядів 582 роки тому
Moment and Shear All Along a Cantilever
From Physics 1 to Engineering Statics: Cantilever Example
Переглядів 962 роки тому
From Physics 1 to Engineering Statics: Cantilever Example
Product to Sum Trigonometric Formulas
Переглядів 272 роки тому
Product to Sum Trigonometric Formulas
1000 Subscribers!
Переглядів 562 роки тому
1000 Subscribers!
Nodes and Antinodes in an Open Pipe
Переглядів 1,5 тис.2 роки тому
Nodes and Antinodes in an Open Pipe
100 cm^2 is NOT 1m^2! Visual Examples in Metric
Переглядів 7702 роки тому
100 cm^2 is NOT 1m^2! Visual Examples in Metric
Hydrogen and Energy (clearing up confusion)
Переглядів 1082 роки тому
Hydrogen and Energy (clearing up confusion)
Force Diagrams Quiz
Переглядів 602 роки тому
Force Diagrams Quiz
How to Clean a Quadra-Fire 1200-I Pellet Insert (Stove that fits inside a fireplace)
Переглядів 1,9 тис.2 роки тому
How to Clean a Quadra-Fire 1200-I Pellet Insert (Stove that fits inside a fireplace)
Deciphering the Definition of Complete Statistic
Переглядів 1,2 тис.2 роки тому
Deciphering the Definition of Complete Statistic
Force Diagram for a Diving Board
Переглядів 2742 роки тому
Force Diagram for a Diving Board
The Definition of Sufficient Statistic Looks Weird (a 2 minute remake)
Переглядів 9382 роки тому
The Definition of Sufficient Statistic Looks Weird (a 2 minute remake)

КОМЕНТАРІ

  • @paulvbg
    @paulvbg 9 годин тому

    Nitrogen has MW of 14 and not 28 as you mentioned but calcs are still based on 14.

  • @covariance5446
    @covariance5446 2 дні тому

    Hold on: I understand you wish to say that little the PDF of Y is the derivative of the CDF of Y (i.e., the statements in the top-right corner of the whiteboard. However, you wrote that F_X(sqrt[y]) i.e., the cumulative distribution function of random variable X as a function of observed value sqrt(y) is 1/(2sqrt(y). You subsequently substituted this expression for F_Y(y) (i.e., the cumulative distribution function of random variable Y as a function of observed value y). is this appropriate? It seems like some amount of explanation would be needed, though? I.e., it seems that you simply used F_X(sqrt(y)) interchangeably with F_Y(y)

    • @covariance5446
      @covariance5446 2 дні тому

      EDIT: Ah, nevermind, I see/am reminded now that earlier, we have a statement equating F_Y(y) to be equal to F_X(sqrt(y)). My attention was darting back and forth a little bit too much between different resources on the computer screen and my own sheets of paper haha. This has been a good struggle; I hope this will help me remember things for my subsequent tests and evaluations :)

  • @covariance5446
    @covariance5446 2 дні тому

    I wonder: Is it sufficient to simply without justification that P(X^2 < y) is precisely equivalent to P (X < sqrt(y))? I know it's obvious that X is SQRT(X^2) and that sqrt y is SQRT(y), but is it also fully defensible to say that P(m<n) is always equal to p(sqrt(m)<sqrt(n))?

    • @robertcruikshank4501
      @robertcruikshank4501 2 дні тому

      That's why I specified a positive domain. In general, if X^2 < Y, then -SQRT(Y) < X < SQRT(Y)

  • @Ritosonium0233
    @Ritosonium0233 4 дні тому

    Provided that Tis symmetric, show that tr ( nabla* T)=0 I am really got confused on this topic

    • @robertcruikshank4501
      @robertcruikshank4501 3 дні тому

      I can see why! I went hunting for definitions. nabla*T seems to be either rank 1 or rank 3 tensor, and in either case I don't know how "trace" makes sense. Trace is a contraction of a rank 2 tensor. When in doubt, study the definitions! You may have gotten a def in lecture or something. Figure out what nabla*T IS in the first place, and what the def of trace for it is. Good luck!

  • @Sidharth-i8f
    @Sidharth-i8f 4 дні тому

    ❤ amazing short and sweet

  • @guilhermebiem582
    @guilhermebiem582 7 днів тому

    The reason why they have to switch it up in general is that the expression P(theta | U, data) = P(theta| U) does not make sense unless you're a Bayesian. If you're doing frequentist statistics, the parameter is not random, just unknown. This means that the expression P(theta) simply does not make sense. This also goes to show how many people are intuitively Bayesian to begin with hahaha.

    • @robertcruikshank4501
      @robertcruikshank4501 6 днів тому

      Yes, I have heard this argument. As far as I can understand (which is limited), it leaves math behind and dives into philosophy. Granted, the philosophy of probability theory is seriously messed up to begin with. It wasn't until I tackled advanced statistics that I realized that I owed QM an apology for calling it nonsensical--it merely inherited most of its problems from probability theory. But to get back on point: if I fully understood the issue you are describing, I would have made another video about it. Sadly I must leave that to better minds than my own.

  • @LwandileAlvin
    @LwandileAlvin 17 днів тому

    Thank you sir Tomorrow I am going to write a paper in Tesla in power systems

  • @attrick4433
    @attrick4433 19 днів тому

    perfect, helped me understand this simple concept more effectively

  • @georgegermanakos6944
    @georgegermanakos6944 21 день тому

    Wow incredibly efficient video, thank you for helping me grasp this topic

  • @isaacmath2173
    @isaacmath2173 Місяць тому

    Thank you I finally understood this 🙏

  • @Thecarshow-ry9cq
    @Thecarshow-ry9cq Місяць тому

    wow , thank you very much, it helps a lot

  • @GauravMehra-l3o
    @GauravMehra-l3o Місяць тому

    Thank you sir very very much for the information and by the way I had a doubt That why is biot savants law only restricted to steady state current flow?

    • @robertcruikshank4501
      @robertcruikshank4501 Місяць тому

      It turns out that electric and magnetic field changes are limited by the speed of light. So it gets really complicated really quickly if you have to take into account exactly when and where the particle was moving how fast, the time lag makes it a mess to calculate. Steady state problems skip all that.

  • @alarmsandamtrak
    @alarmsandamtrak Місяць тому

    As of August 2024, a new fare payment system has been implemented on subways, buses and trolleys. In addition to paying with your charlie card, you can also tap your credit card, or a phone with a digital wallet on the new screens by the fare gate/box. Just make sure to tap your phone/credit card on the screen and your charlie card on the circle. Enjoy the T.

  •  Місяць тому

    Clearest most understandable video I have watched in my life

  • @wilbertchambles
    @wilbertchambles Місяць тому

    Great video!

  • @virtua_t4695
    @virtua_t4695 2 місяці тому

    Very well made!

  • @moizkhan1501
    @moizkhan1501 2 місяці тому

    Thank you. Very easy to understand. Brilliantly explained. Respect from Pakistan.

  • @RoyalYoutube_PRO
    @RoyalYoutube_PRO 2 місяці тому

    absolutely great video

  • @brianleach1392
    @brianleach1392 2 місяці тому

    at 0:31 you say "pressure times volume has the units of work", but the whiteboard says "pressure times the change in volume has the units of work"

    • @robertcruikshank4501
      @robertcruikshank4501 2 місяці тому

      Both are true. Volume and change in volume have the same units.

  • @PreciousOkunzuwa-t1e
    @PreciousOkunzuwa-t1e 2 місяці тому

    Thanks!!

  • @williamkinum6941
    @williamkinum6941 2 місяці тому

    This video was incredibly helpful! Thank you for posting this.

  • @sunilg72
    @sunilg72 2 місяці тому

    I can't explain how much it useful for my exams. I was always confused in batteries one. You cleared all my doubts. Thanks a lot from India🇮🇳🇮🇳

  • @Lexyvil
    @Lexyvil 2 місяці тому

    Thanks! Also for the current we can choose any direction all the time?

    • @robertcruikshank4501
      @robertcruikshank4501 2 місяці тому

      Yes! It's just like choosing a coordinate system, there's no wrong answer. If you get a negative number for your current that means it is actually flowing the other way, just like if you say up is positive and get a negative vertical velocity it means the object is going down. Just be consistent.

  • @emirhandemir3872
    @emirhandemir3872 2 місяці тому

    Wow, this man can explain quantum physics to a toddler! BTW, how did I get here? Oh yeah, I was trying to learn what the f natural gradient is!!!!

    • @robertcruikshank4501
      @robertcruikshank4501 2 місяці тому

      Well, maybe not a toddler, but I did channel Dr. Seuss for it at one point: www.quora.com/search?q=Dr%20Seuss%20quantum

  • @midnightposting
    @midnightposting 2 місяці тому

    You just showed that a commutative binary function is associative iff it satisfies a stronger form of commutativity. It's the first time I see that idea!

  • @Prashhant45
    @Prashhant45 2 місяці тому

    Thanks for clearing my doubt

  • @jacobvandijk6525
    @jacobvandijk6525 2 місяці тому

    The field lines of a quadrupole: ua-cam.com/video/1I_CGFyK5cg/v-deo.htmlsi=gUBuYevLHnP9t3JJ&t=371

  • @lavanyawasnik8719
    @lavanyawasnik8719 2 місяці тому

    Indiaa❤

  • @k.chriscaldwell4141
    @k.chriscaldwell4141 2 місяці тому

    Thanks.

  • @AnuragRana-mw8nl
    @AnuragRana-mw8nl 2 місяці тому

    My teacher taught me complex circuit without making my basics clear so i cant understand that but you made my basics crystal clear

  • @rijannpli9283
    @rijannpli9283 2 місяці тому

    Thanku❤

  • @86ajmn
    @86ajmn 2 місяці тому

    I found your channel googling tesla unit of measurement. Thank you for teaching me this sir.

  • @DYNOPUNCH
    @DYNOPUNCH 3 місяці тому

    This helped me out immensely. Thank you!

  • @adambachert9405
    @adambachert9405 3 місяці тому

    I would give this 1000 likes if I could. Thank you!

  • @johnchakkour
    @johnchakkour 3 місяці тому

    Clear and informative. Thanks

  • @pranavchandrav6071
    @pranavchandrav6071 3 місяці тому

    I'm studying to be an actuary, a big thanks to you for making these!

  • @erhanjaved5903
    @erhanjaved5903 3 місяці тому

    Fantastic Explanation! 😊

  • @Abduzzzzzz
    @Abduzzzzzz 3 місяці тому

    Thnxx

  • @vuthanhphan6565
    @vuthanhphan6565 3 місяці тому

    Thank you so much.

  • @tereshtaymor1404
    @tereshtaymor1404 3 місяці тому

    Bro your a life saver❤

  • @lodgechant
    @lodgechant 3 місяці тому

    What a wonderfully hel pful diagram - thank you!

  • @amnont8724
    @amnont8724 3 місяці тому

    Thanks so much!!

  • @shortskills7612
    @shortskills7612 3 місяці тому

    I saw this video before 3 month it was help full. But I forgot it. Now this time I searched on UA-cam,but you tube don't suggest me so I searched it on Google and found it. Tank you sir

  • @jahshjahsh2002
    @jahshjahsh2002 3 місяці тому

    Why not leave the small x's and y's as they are (not take their logarithms), and try to figure out a good enough equation to describe the relation between them using some other way? (I know the result won't be a straight line and won't be a first degree equation).

    • @robertcruikshank4501
      @robertcruikshank4501 3 місяці тому

      Because how do you measure a "good enough" equation? The formulas we use essentially say, rewrite the variables until we have a linear relationship, then fit the data to the line, and then if need be transform back. You can skip that if you can come up with a better way of defining "good enough" that is quantitative.

    • @jahshjahsh2002
      @jahshjahsh2002 3 місяці тому

      @@robertcruikshank4501 thanks for the reply

  • @suryaks8988
    @suryaks8988 3 місяці тому

    I wonder why it took so long for me to find this channel ❤️ Keep it up Mr. Cruikshank!

  • @cravesman
    @cravesman 4 місяці тому

    you are an absolute legend... appreciate your work!!

  • @mr.dumb1996
    @mr.dumb1996 4 місяці тому

    This is amazing. So simple and straight to the point. Thank you.

  • @existentialrap521
    @existentialrap521 4 місяці тому

    Thx, Doc. We in the streets turning up to this one. Using exponential families right now for most sufficient statistic work, but I am hoping to get this theorem down well. Also, you looking sharp, homie. I like the haircut and fit. Fresh.

  • @taylorhodges8977
    @taylorhodges8977 4 місяці тому

    Stuck on how you got 6.62V @1500resistor. I do .0441*1500 and come up with 66.15. Am I missing something? Thanks.

    • @robertcruikshank4501
      @robertcruikshank4501 4 місяці тому

      Good catch! I missed a zero, since .012/e = .00441, not .0441. Since I had it correct on my calculator, my next calculation came out right so I didn't spot my miscopy.

  • @fiaz8899
    @fiaz8899 4 місяці тому

    wise person