Self Definition and 584 Threads

http://www.foxnews.com/us/2018/03/19/self-driving-uber-car-kills-arizona-pedestrian-police-say.html Considering the small experimental installed base, this gives me serious concerns with the technology. Not ready for prime time.

Hi folks, My question relays on the difference of consumption power of a coil when it's on AC and CC regime. A coild is made of copper wire with air core, aplied on it a CC current of 1 amp, a measure was taked and nottice a 5W of power consumption. Then the power supply is changed to and AC...

Hello PF, I am currently a physics-math junior and I was looking for advice on a small schedule that I am organizing for self-study. Our curriculum for undergraduate physics doesn’t include General Relativity nor approaches relativistic quantum mechanics. I am planning on continuing in...

Hi, I'm wondering how long it took for you and how difficult it was for self-educated/taught computer programmers to land your first computer programming job. I don't care whether it was a temporary/contract job or an internship or whatever. And what did you do to land your first developer job?

Hello everyone, This is my first post and I would like to briefly introduce myself and my situation. I'm 27 years old and a high school drop out, former drug addict, and three time college drop out. I have severe ADHD and insecurities which have made academia too difficult for me to pursue. I...

Hello, currently I am a high school senior who will be going to college in the fall and since my school ends in may and college starts in mid-August. I am planning on self-studying calculus 3, so I can test out of it and go straight into partial differential equations. The textbooks that the...

Hi, I am currently about to begin self studying for UK maths a-levels, however I am also wanting to gain a solid understanding of calculus. I know that calculus is covered in a-levels, but, the books for a-levels seem to be not as dense or as good as the US books I believe. My question is...

I tried to start many books/video courses to learn QFT but this failed because of many factors, including my weak math/physics background, laziness, lack of time, lack of persistence, just to count some. The whole blame is on me, no doubt. Still, if I was able to learn QM to some extent...

Hi, I have recently embarked on the journey to do a mathematics degree. I am 16 and homeschooled, although, I self teach myself as I find it easier to read from textbooks and teach myself the material from resources online and the likes. I have taken a math Gcse a few months ago and was going...

I'm usually entirely autonomous in planning out my curriculum (and have read much great advice here in aid); but my physics curriculum is proving more difficult to plan out than my math curriculum. I was thinking as a start: Kleppner & Kolenkow Mechanics, Purcell Electricity and Magnetism, and...

Hi Forum I am trying to get a better grasp of the relation between electric field and the magnetic field. The overall question is "What is The origin of selfinductance in a current loop?" Here are my thourghts: A battery is connected to a say circular wire with some resistance. The current...

Hi there, I have been searching multiple websites and forums but have not found a cohesive answer to my queries. I am currently going through this textbook to learn pre-algebra: https://www.amazon.com/dp/0618250034/?tag=pfamazon01-20 Also, is this a good book to be studying as an autodidact...

How to calculate following input and output parameters- 1. Input at starter motor - Drive torque and power as shown below 2. Output at flywheel axle - torque, power, Kinetic energy, centrifugal force as shown below Input parameters: starter motor rpm -3600, Gear ratio- 18: 1 if any parameter...

so I recently saw a video where a stick had two flywheels attached on the top, they would accelerate or decelerate based on the pitch of the stick. my question= if you delivered enough impulse do the stick, would the stick stop being able to balance? since the restoring torque is based on...

I'm a 2nd year Ph.D student and I have a pretty good idea what my topic for my dissertation is going to be. It is a very ambitious topic and doesn't fit the mold of small esoteric problems AKA " little problem that nobody ever heard of " in theoretical physics that are the topics of many...

Hello reader, I am trying to learn electrical engineering circuit analysis from Irwin. I am wondering which assignments would help me really understand the learned subjects. I am not a student and I am not going to any university so I cannot ask a teacher. My method for now is doing 3...

I come from totally engineering background but I'm passionate learner in my free time! I would like to start learning from the fundamentals about cancer and see if I can get some insights using my (engineering) background, as I'm progressing more and more in my learning career. Just give me your...

I have learned differentiation (till multiple order differentiation). But I don't just understand integrals.

Homework Statement I have a project for physics that requires me to construct a self-contained egg moving device. It must move itself 0.5m, then pick up an egg (in an egg cup holder), then move another meter and drop the egg off onto a platform 1.0m high, then continue moving after dropping it...

I would have thought that this would have been tested before but this paper suggests that it is a new theory. arXiv:1709.02481 [pdf, other] A possible explanation for dark matter and dark energy consistent with the Standard Model of particle physics and General Relativity A. Deur Comments: 6...

It seems that it is self evident. After all, a set A consists of things. These things exist as part of the set. Therefore the idea is that I can think about the item of the set without really thinking about the other items in that set. The set is in a sense the totality of the parts. Why is this...

sorry bout long lead up retractable cords, pet/id leashes and tape measuers work the same way they have a really long metal band coiled inside, anchored on 2 separate pieces this coiled up band of metal gets tighter as you pull, and tries to uncoil when let go my questions/problems are as such...

Hello Physics Forums! I'm in a little bit of an interesting situation. I've completed the classes offered at my school, but have been told that if I can directed-study these four courses they will provide me with a credit bearing exam for college undergraduate credit. Do you have any...

Hello, I want to learn Physics, starting from mechanics to quantum mechanics and such. My brother is a physics student and he uses the University Physics text. This seems to be extremely popular- all my friends have also studied with this text. Is this a good book to get and start from page 1...

Hi all, For those of you who work in field like software engineering, data analysis, and other tech industries, what measures have taken to make sure you'll always have a job in the face of automation. I know at my core what I would want to do if academia isn't an option after my PhD is work in...

As the title says I want any tips or advice on self learning Basically IT ,ENGINEERING and science

Homework Statement An alternative to the usual no-slip wall boundary condition ##u = 0, v = 0##, is the porous-wall condition ##u = 0##, ##v = v_w(x)##. A porous wall with negative ##v_w## (suction) is known to delay transition to turbulence, for example. 1a) Assuming a uniform ##u_e(x)##...

I've recently completed Calc 1 and 2 on my own, with little guidance outside (which I feel hurt my final exam scores), but I attribute this primarily to the lack of a good textbook. I decided to hold off on Linear Algebra and Multivariable until I've graduated, and now that I have I'm looking to...

I am self -studying SR with Books written by Resnick and A.P.French. Is that o.k. or should I take some another book? I am asking this because there are no. of books suggested on P.F., but these suggestions don't include Resnick and A.P.French.

I was admitted to a very good undergraduate physics program (Columbia University), but I think I would like to take a gap year (defer my admission) to prepare my self better. I do feel a bit intimidated as I come from Colombia and I would prefer it if I could further my studies before going to...

Hello, everyone, I am a 16-year-old high school student studying AP physics, that will be a senior this coming year, I have a very keen interest in physics and would like to pursue a career as a particle physicist. I finish school in 2 weeks (finals) and I want to study physics over the summer...

I am a high school student entering 11th grade soon. I will be taking calculus ab (calc 1) in school, but I am wondering if it is possible to self study calculus 2 and take it over the summer at a cc?(and do well!) If everything goes right I want to do calculus 2 the summer after junior year and...

Hello All I am designing some very basic components for a motorcycle project at home, and because I am interested, thought I'd use it as an opportunity to refresh my memory in order to reduce the risk of the parts failing. To begin, I want to do some basic hand calcs if possible so have...

I am a physics student going into my 3rd year this fall. Over the summer I want to go through my textbooks and study them. My plan is the following University Physics (Young and Freedman): The first 10 odd end-of-chapter problems from every chapter (440 problems total) Then do the first 5 even...

Hi everyone, I am currently a physics and applied maths major in Australia. I am studying part time as I am also an athlete and spend a lot of my time traveling and training. Because I am studying part time, I have been self studying alongside my subjects and on the semester breaks and while I...

Hi For a book I'm writing, i try to write a very very very detail proof of self-buckling. I did it almost by taking inspiration of: https://en.wikipedia.org/wiki/Self-buckling But i really really don't get how we arrive to, that when, x=0 as we obviously must have: \dfrac{\mathrm{d}^2...

Homework Statement A thin hollow cylinder of radius a is surrounded co-axially by another hollow cylinder of radius b, where b>a. An electric current I flows through them (I is into the plane of paper (x) in outer cylinder and coming out of plane of paper (.) in inner cylinder). Find the: a)...

Hello,first time posting a thread not just here but generally so i'll try my best. So while i was in class we were learning about square roots,at first it seemed fairly easy,but when i asked my math teacher how do we find them more easily, he smiled and talled me:"The problem is,you just...

Hi. Superconductors can be made hover above or even below magnets. As far as I know, this can be interpreted as an extreme form of Lenz's law: Eddy currents on the surface of the superconductor create an opposing force that is able to cancel gravity since the currents aren't affected by...

Hello, In classical electromagnetism, we learn that an electric charge generates and electric field which other charges can feel through a force. But the source charge does not feel its own generated electric field. In reality, a charge feels its own field. Why are we able to ignore this...

A varying magnetic flux causes an induced voltage (according to Faraday-Lenz law) that generates a current that generates a magnetic field that generates another magnetic flux in the same circuit. Does the Faraday-Lenz law include this self induction? In other words why can't we take that...

Hi, I am going to attend A level exams as a private student by january 2018 in the subjects of mathematics, physics, chemistry and biology. I have planned to study 2 hours per subject in a day. By evening I would go to coaching classes in all subjects except biology, that would be 3 hours of...

Hello everyone! I found in my textbook that in order to calculate the pressure experienced by the surface of a long straight solenoid with ##n## turns per unit length and current ##I## we don't use the typical magnetic field ##B=\mu_0nI## on a loop of the coil , but a corrected magnetic field...

Homework Statement Given two inductors, connected in parallel connected to a battery, why do the following emf relations hold? $$\mathcal{E}_1 = - N_2 A \frac{d B}{d t} = -M\frac{d I_1}{d t } \\ \mathcal{E}_2 = -L_2 \frac{dI_2}{dt}- M \frac{dI_1}{dt}$$ See attachment ! Homework Equations...

Hello, I 'm trying to perform alloy of FeCr (Iron-Chrom) with calculate self diffusion iron depend with chromium composition. My work result that chromium doesn't give linier function with self diffusion iron in the alloy of FeCr. Maybe, anyone can tell me what's happened with my work. I'm so...

Hi all, In Peskin's book, Chapter 7, the self energy of electron has been calculated. In Equation (7. 28) ##p\!\!\!/## set to equal the mass of the electron ## m_0 ##. What if I calculate the self energy of a massless fermion mediated by a loop of another massless fermion and a scalar, like the...

I am planning on doing physics as I go through calc2/3/ODE/PDE. I bought University Physics and the Resnick/Jearl Physics book, and frankly I want something a bit higher level.. more like Kleppner/Kolenkow. I was thinking about getting the K&K book, but some people are suggesting Morin...

Hi all , I try to calculate the squared amplitude of the following self energy digram : where se is massless Dirac fermion , and vrm is massless right handed neutrino. x is a scalar with mass m .. I wrote the nominator of this process as: N = ## \bar{u}(p) (1-\gamma_5) (p\!\!\!/ +k\!\!\!/ )...

Hello everyone. What measurements have been done of the Higgs self-interaction? If nothing has been done yet, what are the relevant groups and research articles describing the progress of work in this direction? If this has been done, I would love to know the references. Thanks!

Hi, I am only 13, but am really interested in physics. My highest level of math knowledge is pre-algebra, but I'll be in algebra 1 once school starts. I am a fast learner and know I can learn the physics criteria if it is explained thoroughly. Please don't let my math knowledge make you think I...