Basics Definition and 379 Threads

TL;DR Summary: Hey everyone. I need help with clearing my concepts of mechanics. I am really confused. Are there any good books which can make me understand concepts in a better way? Book recommendations for mechanics (for improving basics).

TL;DR Summary: linear algebra confusing & hard; how to study right? I plan to return to linear because that was one of the classes that you couldn't just try to shamble your way through somewhat. multivar calculus theorems still make some sense visually. Linear algebra exams were like trying...

This is a very basic beginner question but one which confuses me. We are told that voltage = current x resistance but I've also read that we can have a voltage without current. But, if current = zero, then if V = IR, V must be zero. Can someone explain where am I going wrong?

Hi, everyone! I'm planning on restudying math from the beginning (K-12), via KhanAcademy, MathIsFun, and plenty of other resources. Now, what I'd like to ask is, as the title says, should I study material grade by grade or topic by topic? Additionally, is there a way to test myself to know...

Hello everybody ! I do have a problem understanding transistor. I know how these solve and work : I know some basics like the voltage on Rb is Vbb - 0,7V. Or something like this. I also Know that the maximal current in this transistor is "defined" by the resistor in the collector which is...

I'm new to this forum and I'm not sure if I have chosen the correct subject heading. I watched this Youtube video showing how 2 helium filled balloons sank in a vacuum chamber. The presenter used this to prove that helium would sink in a vacuum. I think he was wrong. It was the balloons that...

I have a VNA with an SMA connector for measuring reflection. If I connect only the center conductor of the SMA to a piece of metal, I get a spectrum. My question is, what should I be doing with the outer connector? I am trying to learn EE by reading and doing. I don't have a lot of intuition...

I have just started my electrician career and I am studying electric motors. why an 120v ac motor can not be 3 phase ? .

When I ask on the Internet what the computer is and how it works, there are a lot of articles and videos and I watch them, I read them, and most of them I see other articles and other videos, so I can't learn. Can you help me out a little bit?

I know this will demonstrate how ignorant I am about the current state of string an brane theory, but I have a question that I don't think I could find the answer in current discussions. Please don't be too harsh. A string has to come in one of only a few "types": Closed - the string is...

Hey everyone :). after studying c++ and a bit of phyton in the university (not in a career related to programming), I was wondering what to study after the basics. youtube tutorials are at about the same level as I was at (inheritance, class, pointer), not more advance... what is the...

I've been screwing around with an embedded esp32 system and have successfully flashed a few firmwares. The trouble is, my particular hardware has a built in usb port. For my next project I want to use a wifi esp32 board with camera peripheral. There are quite a few of them on Amazon and a...

Ok, sorry, I am being lazy here. I am tutoring intro topology and doing some refreshers. Were given the subspace topology on [0,1] generated by intervals [a,b) and I need to answer whether under this topology, [0,1] is Hausdorff, Compact or Connected. I think my solutions work , but I am looking...

Hello. Questions: Are antimatter, dark matter, negative mass confirmed that they exist and exhibit as phenomena? What about dark energy and negative energy? Do these types of matter behave as wave also? Do they exhibit such behaviour? About those types of energy i said, can they be transformed...

Spacetime diagrams seem to be the most used explanation for relativity weirdness, so I’d like some clarification in how to make them, it anyone wants to help. (1) Light’s worldline is 45 degrees, obviously. No issues there, I don’t think. (2) How do I determine the angles of the moving frame...

Summary:: Random processes, autocovariance, ergodicity, Gauss-Markov etc Hi I am a person who resolutely prefers depth over breadth, and currently I am trying to learn more about random signals and Kalman filtering. However, the books I have found so far will mention and superficially...

Is Cosmology in a basic level more difficult to understand than the other areas of General Relativity? By "basic level" I mean, in the way the subjects are presented for example, in Weinberg's textbook: Gravitation and Cosmology, Principals and Applications of General Relativity .

Hi I have some questions about the center selection problem: 1) K= 4, Are we finding the center of 4 circles? 2) r(C) = maxi dist(si, C) = smallest covering radius. In case of r(C), I can’t understand what is meant by ##max_i dist(s_i, C) ## How the max will work? Some body please guide...

I want to learn physics and mathematics from the absolute basics to the highest level.Please suggest books and online courses.From basics please.

My question is as it is as you have read in the heading and please tell me in taking mind that I am not a calculus master but just a beginner.

Hi all, I'm trying to understand basics of radiofrequency (RF) coil development for magnetic resonance imaging (MRI). For example, the problem is to develop simple surface single-loop RF coil tuned to 100 MHz. In program Coil32, I set the following parameters: diameter of the loop D = 20 mm...

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Hello, I need some help on understanding what this book is trying to convey. How does "any part of the spring acts on another part"? Doesn't (2.25) just give us the "operator force" and, since the spring is at equilibrium, the elastic force? What exactly is strain? And I am failing to see the...

Not sure if this thread belongs in this section. I was thinking who could give a better advice than the teachers themselves? Please do move the thread if it does not belong here. Thank you. I am first year non-physics student. I kind of never had any experience with physics. I have about 3...

I tried learning calculus using the book by Spivak.In this text, while introducing integrals the author explained a lot about partitioning the area under the curve and defined the integral.The way I understood this is, as we increase the number of divisions in the partition the lower sum and the...

Greg Bernhardt submitted a new blog post Lie Algebras: A Walkthrough the Basics Continue reading the Original Blog Post.

Please could someone give me some idea of what is happening when you pull back on a syringe filled with fluid and the bubbles in the fluid (in the syring) expand? Let's assume it's water. How do the bubbles grow? I am assuming it is a rectified diffusion process where gas in the fluid is drawn...

Hi, before posting I did a search both on google and here, there is not that much info out there. The basic spheromak configuration that I could find resembles a tube with an inner electrode and and outer one (plasma gun) and a chamber at the end where the "plasma ring" expands into once it's...

Hi, Just wanted to see if I understood the meaning of Generalized Linear Models: In the case of Standard ( "Non-generalized") Linear models, a dependent variable y is a linear function of a dependent variable x. In a Generalized Linear Model (GLM), a dependent variable y is linear in some...

I decided to read up on the chapters we didn’t cover in first year Physics from my textbook, and decided to start with general relativity since it was in the same section of the textbook as the last topic we covered (that topic was physical optics - not lenses- photons and the double slit...

I started studying distribution theory and I am struggling with the understanding of some basic concepts. I would hugely appreciate any help, made as simple as possible, because by now I'm only familiar with the formalism, but not all the meaning behind. The concepts I am struggling with are...

Homework Statement So i have a few scenerios on my physics prelab that I want to clear up and understand. 1) What happens to the temperature when you heat up a solid metal much below its melting point? 2) What about when the solid metal starts to melt (and you are heating it still)? 3) What...

Homework Statement We release m_o = 1 kg object from h=1m height. How much does the Earth move (x)? I just need the comfirmation if I did correctly? Homework Equations Conservation of momentum: m_o v_o + m_E v_E = 0 The Attempt at a Solution I wrote the energy conservation law as (beginning...

What is basic and advanced physics mechanism behind this ceiling can? Why it rotates in one direction? Why it can't rotate reversely ? How air is supplied by this fan ?

Suppose we are asked to find the time period of vertical oscillations of this system. Then should we find the component of displacement along each spring and then add the forces by vector method or should we simplify the diagram into series and parallel connection like in electrical circuits and...

Which programming language would you like being taught if you were a very young person (5 to 7 years old), as a first programming language? Worded differently, which programming language would you like to teach to your son/daughter if he/she was that age? I've heard about Scratch and Logo. Then...

Hello. I have been interested in radios lately and wanted to make one by myself. I know that it requires a lot of knowledge in physics and electronics, but what basics do I need to know? Frequency, antennas, voltages... Could there be any legal issues? I live in Australia. I am only a high...

Hi there! I'm looking to create a small (max 20 foot range) radio transmitter, to direct a focused radio beam at a receiver, for the purpose of remote switching. Ideally, I would like the device to work at a relatively "exotic" frequency, as I would think there is a lot of radio noise where I...

Hey guys! I am currently working on some tasks to improve and expand my skills, but I can not go on with the following task An Nd-YAG laser (D=5mm diameter) is focussed with a lens (f = 200mm). I: How big is the laser beam at its waist? (Solved) II: What is the largest bundle behind the lens...

Hey guys! I hope my English skills are enough to describe my problems sufficiently.(Homework Statement ) I. Following the following picture, what wavelength should a laser be used to process aluminum? II. What metal surface can be cleaned with a frequency-doubled NDYAG laser? To I: The...

I have a couple of college algebra textbooks , but none has some proper intro to logarithm basics . I like to keep a book for logarithm alone , i see some online PDF's on logarithm , but all are sort of messed up . Please help

This is a snapshot of the diagram in the high school textbook. and here is the accompanying text I would like to understand the "minus" signs in - N1dΦ/dt and - N2dΦ/dt This is my understanding - When there is a crest of the sinusoidal voltage i.e top terminal of the input voltage is...

Can somebody please explain me the basics of resolver. How it works? How it calculates angle and velocity? Atleast any proper links. Please help.

Homework Statement Ex. 2. Express each of the following by an equation: (a) Two vectors A and B are parallel. (b) Three vectors A, B and C are co-planar. Homework Equations C = A + B 3. The Attempt at a Solution I understand (a) the answer being B = (alpha)*A because that is a scalar...

Do you regard relativistic effects to be physically real or just apparent (kind of like optical illusion caused by distorted information one is receiving)? To prevent endless entanglement in "define physically real" arguments imagine this: two spaceships moving inertially relative to each...

Homework Statement http://www.brighthubengineering.com/hydraulics-civil-engineering/55054-open-channel-flow-basics-hydraulic-jump-calculations/ In th earlier part of this notes , i was told that the The hydraulic jump is an abrupt transition to subcritical from supercritical flow. but , in...

I am reading Kenneth Ireland and Michael Rosen's book, "A Classical Introduction to Modern Number Theory" ... ... I am currently focused on Chapter 12: Algebraic Number Theory ... ... I need some help in order to follow a basic result in Section 1: Algebraic Preliminaries ... The start of...

I am reading Kenneth Ireland and Michael Rosen's book, "A Classical Introduction to Modern Number Theory" ... ... I am currently focused on Chapter 12: Algebraic Number Theory ... ... I need some help in order to follow a basic result in Section 1: Algebraic Preliminaries ... The start of...

Can anybody tell me some of the best book for quantum mechanics which starts from basics to advance level

My understanding of physics and mathematics and what nots is self taught and frankly really rather amateur compared to the people who use this forum, but one thing that really fascinates me is the holographic universe theory. Would you be able to explain the pros and cons of the arguments and...