Reading Definition and 636 Threads

Homework Statement I have successfully opened and discarded the headers. Then I calculated the distances between point 1 and others and the minimum distance as well. However, I am not sure how to make the code work for more than 4 points. The attached text file is what I am trying to read and...

Hi, I am using fortran to read specific columns from a .csv file. the rows in each columns are different, so I wish to read columns wise with a do loop. say, I wish to read from A1 to D20 initially(4 columns of 20 rows), then later f1 to h35 (3 columns, 35 rows). how do I read particular columns...

Hi, I'm studying physics and was wondering about the light meter I used. It was set to 2000 so I could get readings, instead of 2 because the readings wouldn't show. Does this mean my values I get from the light meter is in mLux (milli) or just Lux?

Homework Statement The potential difference across resistance R carrying current I is V = IR . Now if the potential difference is measured via voltmeter of resistance r , the reading on voltmeter is V' . Prove that V' = Ir/(R+r) . For what value of r does the voltmeter measure true value...

Homework Statement The weight of a glass full of water is being measured using balance. a. An object is fully immersed so that some of water spilled out. How is the reading compared to before the object is immersed? b. If the experiment is repeated and now the object immersed has same volume...

Homework Statement the question asks for the concentration of ethanoic acid, therefore I need to find out the volume of ethanoic acid used during the titrations. I thought it would be 30mL because that's when the temperature reaches maximum. But the answer says that the volume should be in the...

Hi all, I have been trying to read up on quantum foundations after being first introduced to it on this Perimeter Institute page: https://www.perimeterinstitute.ca/research/research-areas/quantum-foundations/more-quantum-foundations However, I have had difficulty finding notes and papers on...

Hi everyone. This isn't for a class but more for lab work. I'm confused on how to read optics diagrams to understand this Glan-Taylor prism, specifically the up and down arrow vs the dot. Does the arrow pointing up and down mean that it is vertically polarized. Is the dot horizontally polarized...

Hey guys, new here and was hoping for some help. Basically I have to use Fortran 77 to complete some questions for an assignment The first thing to do is, read a bunch of numbers in a list format and then use these numbers to be entered within an equation. The values I have are listed in a 1...

Preface to thread: The multimeter is set to read resistance in all the scenarios I ask about in this message. The word "COMP" in the ladder diagram stands for compressor motor. The three letters underneath the capacitor are DRC, which stands for Dual Run Capacitor...

Hello All, Wanted to see if I am approaching this problem correctly, I have an exam coming up and am pretty sure something like this will show up. Examine the phase diagram (phase.jpg) with a 20WT% A and 80WT%B which is allowed to cool slowly from liquid A) what temp does the first solid...

Can one explain to me the sentence: "Transitivity (or transitiveness) is a key property of both partial order relations and equivalence relations.". ...in simple words. The sentence is from Wikipedia at address: https://en.wikipedia.org/wiki/Transitive_relation

Can somebody simply this sentence: there are relationships among the angles of a pentagon and its diagonals. For example, the ratio of distinct interior angles to distinct diagonals is exactly 1 : 2. ? Can somebody explain it in simple words, please...

I don't send text message on my phone or pay much attention to text messages that arrive on it. However, I'm curious about the current state of text message technology. I'd think there is a great demand for the ability to read phone text messages online. From glancing at this topic on the...

I have this odd difficulty when it comes to vector calculus. No matter what I do, seeing these equations just stays daunting. Its a massive effort for me to read them, and when I say "read" I mean look at the equations, and actually understand what it is it wants me to do. Now as with most math...

Hello, I've got a voltage comparator, well only on schematics, I need to chose one and I need some help interpreting datasheet. The datasheet I was looking at is of a lm393. My input voltage ranges from -7.8V to +7.8V. The datasheet says -0.3 to something. So it's not usable, right? I was also...

Hi, I have a 2004 Toyota Matrix with 270 000km. It's working great but today when i started my car the battery was going up to 17.2V (i have a battery voltage reader in the car at all time). It's the first time it went up there, it usually stays in the 13-14V. I know something is wrong and I...

Hi all, i have stumbled across a drawing which referenced DIN 16901 for its tolerance. I have a table of DIN 16091 which i don't understand. For the first half of the tables, the tolerances are + and -, which i understand. The second half (tolerances on dimensions with Deviations entered...

Be sure the visit the Sundial Bridge at Redding, California.

I just like to read and know, and still, I realize that there have been so many works in mathematics and so much to study which I don't even know of. Is there any way I can keep a track of different mathematical works so that I can read them. For example, it was not very late when I came to know...

Hello. Please, take a look at the screenshot from the textbook. They say in the textbook that there are in total 48 data observations, 20 of which lie in the interval 0 - 2, and 6 lie in the interval 2 - 4. Yes, both 20 and 6 are more or less clear on the graph, but how did they come up with 48...

All, I hope this is in the right forum. I'm a bit embarrassed that I cannot make sense of this graph. My question is this: When looking at the graph, should you ONLY be reading data points from the two lines -- but also reading the lines independently? I am at a loss why the atmospheric...

Is it ok to refer to a papers published by a different academic, or should i mainly be talking about my potential supervisor's published papers in my interview? thanks

Homework Statement For a circuit with 3 resistors in series (R1=1.00 kOhms, R2=2.50 kOhms, R3= 4.00 kOhms and Va=12.0 V). A voltmeter was placed across R2 and R3. Calculate the relative error in the voltage reading if the internal resistance of the voltmeter was a) 5000 ohms, b) 50 kOhms, C)...

Hello! I see this Steam table: It shows Vg but not Vf. It mentions some equations at the bottom. Does anyone know how much is Vf for 0.1bar?

Homework Statement Homework Equations For question 14 PMMC measures average value MI measures RMS value The Attempt at a Solution I think PMMC should give 0 V But book answer is B i.e 1 V (where am I wrong?) and MI should give 1.414 V. For this book answer matches my answer.

Often when I read a chapter in a textbook and don't understand something, I find "reading notes" by other students extremely helpful. Oftentimes in these notes other readers have simply written down summaries of the sections in their own words. These descriptions of the "same thing" in...

Hi, I recently have been trying to look into whether or not white noise works as a means to block out external sounds so i can concentrate. However, I want to know whether it actually impairs studying and reading. I do not care if it has no benefit, as long as it has no negative effects. I am...

Homework Statement There was the times 100 years ago, N.Herreshoff was designing giant J Boats, America s Cup boats by only carving a wood piece in few hours ,without drawing calculating anything and builders were measuring the wooden half model and building a multi million dollar yacht wins...

https://www.ma.utexas.edu/users/dafr/OldTQFTLectures.pdf I'm reading the paper linked above (page 10) and have a simple question about notation and another that's more of a sanity check. Given a space ##Y## and a spacetime ##X## the author talks about the associated Quantum Hilbert Spaces...

Hi, I'm currently in "gymnasiet" in Denmark, which I understand is similar to high school in the US. It's what gives you access to universities, so to speak. After "gymnasiet", which I'm done with summer 2019, I'm planning on going to university for a physics degree. I'm currently taking...

These are the links to the specific product I am looking at and its noise characteristic graph. http://www.emelectronics.co.uk/a20.html http://www.emelectronics.co.uk/graphs/a20graph.htm I understand the graph for the most part, but I am confused about which one of the four filters that are...

Hi, I need to find the peak voltage of the ac current produced by the sensor connected to the alternator on my motorcycle. The workshop manual recommended a peak voltage adapter which goes on a multimeter. I don't want to buy this expensive thing. I was wondering since Vp=Vrms*sqrt (2). I can...

SOLVED Hi there. I have the elements of a matrix written in a txt file (in row major order). I need to read this matrix to use it in my fortran77 program. The text file contains the elements written in this way: A(1,1) A(1,2) ... A(1,N) ... A(N,N-1) A(N,N). I was thinking in doing a do loop...

Hi, I had a project in mind but I'm not sure its possible, or what I might need. Current Setup: A small loop antenna monitors a 24kHz (VLF) radio signal, and passes it to an amplifier (schematic can be found here: https://www.physicsforums.com/threads/schematic-symbol-help-supersid.709128/)...

I am a college student taking Physics 101. I am currently reading Physics Fifth Edition by James S. Walker. Have any of you guys used this textbook? How should I study? Do I do every problem in the back of the chapter? And if it requires hours of consistency, do you recommend I stay up and force...

Dear folks Yes I do understand scale ration 1:25 means 1 unit on a map equal to 25 units on a real and scale ration 1:75 means 1 unit on a map equal to 75 units on real Question my Kent tri scale ruler for the ratio 1:25 showing first number as 0.5 m (i.e 50 cm, 500 mm) While first reading...

Homework Statement Hi, I have a question about uncertainties. If I am carrying out an investigation I need to record my uncertainties in each measurement. I am aware that instruments have reading errors. So, if I use a stopwatch to measure the time period of a pendulum the reading error is...

Homework Statement Homework EquationsThe Attempt at a Solution Part a) Voltmeter can be replaced by an open circuit and ammeter can be replaced by a short circuit .By doing so the current flows in the outer loop consisting of both the batteries and both the resisters .The current in the...

Homework Statement In this circuit What will be the reading of the ammeter and that of the voltmeter when: 1. Key S1 and key S2 are open. 2. Key S1 and key S2 are closed. 3. Key S1 is closed and key S2 is open. (Neglect the internal resistance of the source) Homework EquationsThe Attempt at a...

Hi all, I am currently working on an Arduino project that involves multiple stepper motors. The motors are told how to move by an external txt file. However, sometimes the processing of how the steppers have to move takes longer than the actual movements themselves. Some movements should only...

Hello! Can someone recommend me some good reading about Lorentz and Poincare groups. I would like something that starts from introductory notions but treats the matter both from math (proofs and all that) and physics point of view. Thank you

Homework Statement The current in coil P is constant. An iron rod is inserted into coil P. Coil Q is placed next to P with a voltmeter connected to it. Explain why, during the time that the rod is moving, there is a reading on the voltmeter connected to coil Q Homework Equations emf=-Dphi/dt...

What book are you reading now, or have been reading recently? Only STEM (science, technology, engineering and mathematics) books are counted.

Hi All, I needed some help or guidance starting my MSc reading, as there is tonnes of literature out there and it's difficult to understand what is necessary. I am beginning to look at applying screening models to a 2D system, such as the Thomas-Fermi continuum screening model, to a 2D system...

I am reading Feynman's book QED: The Strange Theory of Light and Matter". What I am getting out of this is that a photon is like a tiny harmonic oscillator traveling through space. Each harmonic oscillator has frequency and phase. If two photons have the same source and start out nearly in...

Does anyone have any good reading strategies which they use to plough through academic papers? I'm currently a little bit daunted by the amount of stuff out there that would be worth reading, and it's almost paralysing me a little. Advice on any of the below would be useful: - Deciding what to...

Hey I was wondering if anyone had an idea of where I should start reading to learn a little about astrophysics or theoretical physics (or anywhere else you think I should start if that seems too challenging to start with). I don't consider myself to be very educated, I grew up in a devoutly...

Suppose a container is full of water is placed over a weighing machine. Now a ball is hanged with massless string but dipped inside the tank and ball is not touching the bottom. What will be the new reading on the weighing machine?

Hey everyone. I'm a senior in high school who is taking AP Physics C, and I love physics. I've already known pretty much everything in Physics C (apart from some calculus derivations in E&M) from self-study, and I've studied astronomy and astrophysics a lot throughout high school as well. I've...