# What is Intro: Definition + 563 Threads

The Intro is the debut EP by Canadian singer/songwriter Ruth B. It was released on November 27, 2015, and was met with generally positive reviews.

View More On Wikipedia.org
1. ### Discovering a Community of Physics Enthusiasts: How Did You Find Physics Forums?

I found physics forums simply well by searching up "Physics Forums" because I was stuck on a (Fairly basic) question from a text book whilst practicing mechanics Questions, Nuff said ay? I already feel like this is a community I will enjoy being a part of as I have read through the support given...
2. P

### Forum Guidelines: Rules and Expectations for Scientific Discussions

Hello! My name is Eleonora but you can call me Leo. I'm a girl. I love mathematics and physics and I aspire to become a theoretical physicist one day (or maybe this will change someday, but for now it's my biggest life goal). I still go to school. I want to self-study physics and find fellow...
3. ### Intro to Linear Algebra - Nullspace of Rank 1 Matrix

The published solutions indicate that the nullspace is a plane in R^n. Why isn't the nullspace an n-1 dimensional space within R^n? For example, if I understand things correctly, the 1x2 matrix [1 2] would have a nullspace represented by any linear combination of the vector (-2,1), which...
4. ### I Understanding Diffraction Condition in Kittle's Intro to Solid State Physics

I am going over the diffraction condition section in Kittle's Introduction to Solid State Physics physics and I am having a hard time understanding why the phase difference angle for the incident wave is positive while the phase angle difference for the diffracted wave is negative. Thank you...
5. ### Advice for self-study Intro to Mechanics course?

TL;DR Summary: Is there a mental model for setting up equations of motion and related mathematical equations when tackling mechanics problems? Hi there, I'm going through a first year mechanics textbook (An Introduction to Mechanics by Kleppner et al) from MIT OpenCourseware as I'm interested...
6. ### Comp Sci 8 bit block division -- University Level Intro Course: Networking

What I think I should do: 1 = 0001 7 = 0111 3 = 0011 First block = 00010111 Second Block = 00110000 Now, I do binary division 00010111/11010 = find the answer 00110000/11010 = find the answer This is what I think I should do, but I am not sure if this is correct. Is this basically CRC? Any...
7. ### Comp Sci Parity Check Question -- University Level Intro Course: Networking

What I know: Parity check is used to detect if there are errors when transmitting data by adding redundancy bits to the dataword (data that we want to send) which creates a codeword. Then the receiver checks if the 1's are even or odd and based on that, we know that there was corruption during...
8. P

### Who is Parthi and What Does He Study at PSG Tech?

Hello science people I am Parthi, Mechanical engineering student from PSG tech, Tamilnadu, India.
9. ### Intro to quantum mechanics - Spin and linear algebra

So this expression is apparently in Sz basis? How can you see that? How would it look in Sy basis for example? The solution is following. They are putting Sz as a basis, bur how do you know that Sz is the basis here? Thanks
10. ### Intro to Quantum Mechanics - Formalism normalisation

I can't figure out how they get i/sqrt(2) for normalisation of c1. Why is it a complex number? If I normalise c1 I just get 1/sqrt(2) because i disappears in the absolute value squared. Thanks
11. S

### Maximizing Student Success: A Forum for Secondary Math Educators

I am secondary math tutor and found this forum very useful.
12. ### Plot the Expectation Value of Spin - Intro to Quantum Mechanics Homework

I have found an answer to all of them (a-e) but I don’t know how to plot the function. Thanks!
13. ### Intro Quantum Mechanics - Dirac notations

I am learning Dirac notations in intro to quantum mechanics. I don’t understand why the up arrow changes to down arrow inside the equation in c). My own calculation looks like this:
14. ### Intro text on building a small fluid pressure chamber?

As stated in the summary, I'd like to design a chamber to store water under pressure. Nothing too powerful - basically at the level of a super soaker, maybe a little higher. The trick is, I want it to be powered and controlled electronically. But, I come from electronics land and know nothing...
15. ### How much of first year Intro physics do you remember?

Summary: I am just curious I know 🧐 Im coming up the end of intro university physics mechanics chapters. It has been quite enjoyable, especially chapters on energy, momentum and fluid mechanics. There’s so much information packed into these chapters though. I am wondering what was your...
16. ### Requesting guidance on Commutators & Intro QM

I have approached this question step by step as shown in the image attached. I request someone to please guide if I have approached the (incomplete) solution correctly and also guide towards the complete solution, by helping me to rectify any mistakes I may have made. I'm still unsure how to...
17. ### Question on Intro QM pertaining to Harmonic Oscillator

Hi. I have attached a neatly done solution to the above question. I request someone to please check my solution and help me rectify any possible mistakes that I may have made.
18. ### Need to cut back on the time I spend self-studying each Intro Mechanics chapter

These are all the chapters for introductory mechanics in my textbook. What I have been doing is reading the chapter then following it up with watching a tonne of lectures and worked examples on that topic and attempting to do the problems. I’m on Applying Newton’s laws and I’ve been studying it...
19. ### Cracking Exams: Overcoming Knowledge Gaps for Intro QM

Summary:: I understand the consensus on PF about studying for knowledge and not merely for "cracking Semester Exams" but I urge you all to go through below thread before attaching to that feeling in my case. Hi. So I have my Exams on Intro QM approaching very soon, which will be a combination...
20. ### Engineering Overarching Intro Engineering Textbook

Is there any sort of textbook that covers multiple engineering areas that is at an introductory level?
21. ### Quantum Finding the Perfect Self-Study Book for Intro Stats & Quantum Mechanics

Can you please suggest a good introductory statistical and quantum mechanics book which can be self studied. My math background : I've done multivariate calculus, vector calculus, linear algebra ,some complex analysis all at the usual undergraduate level. The books I've self studied thus far...
22. ### Intro Physics homework help - distance and velocity

I have tried this problem over 4 times and keep getting the exact same answer, which is incorrect. Could someone please help by pointing out what I did wrong, or letting me know if I am actually on the completely wrong path? Thanks! Have a wonderful day :)
23. ### Problem using Griffiths Intro to Quantum Mechanics

Summary:: The problem solutions contain a lot of unjustified steps, making them pointless. I am trying to use Griffiths Introduction to Quantum Mechanics. He states that the wave function ##\psi## approaches 0 as x approaches infinity to make normalization work. I can accept that. But then I...
24. ### What is the relationship between epsilon and sigma in multi-ferroic materials?

I have a TA that is ignoring me, so I have to resort to this online forum. Also, a very unhelpful example from lecture (just 1). I have some other equations, but I don't really know how they all tie together. I find epsilon = 10um/1mm (both materials are 1 mm in length) = 1E-2mm/mm sigma 2 =...
25. ### Intro special relativity problem regarding time dilation

This example is worked out in the book, and at the beginning, they make the assumption that the muon is traveling at c, and then find the change in time from the Earth reference frame using delta t=100km/c. Then delta t is plugged into the time dilation equation on the left side and we solve for...
26. ### B Value of this 'Science' Channel as quick intro

I found, what appears to be, a good channel on General Relativity and other science topics. I'm dubious because... the internet. I'd love a second opinion on whether this channels first few videos on The Maths of General Relativity are doing it justice. I'm a dad with a day job and I can't...
27. E

### Other Looking for a Materials Science Textbook?

Hi, I just wanted to know if anyone has any experience with a textbook that deals with topics like crystals+lattices+symmetries, diffraction, microstructure, mechanical behaviour of materials, etc.? Thanks.
28. ### Integrate (xsinx - cosx)/x^2 with Intro Calc Techniques

I'm pretty confused here because after getting stuck on this problem, I tossed it into an integral calculator and it said the answer was 2 Si(x) + cos(x)/x + C. In intro calc we definitely haven't learned the Si(x) function or even gotten to any of the Taylor polynomial stuff yet. I tried IBP...

31. ### Intro Math Suggestions for an Intro to Proofs Math textbook for Self Study

Hi everyone. I'll be taking a course in the fall called "Introduction to Mathematical Reasoning", which is basically and introduction to proof-based mathematics. The syllabus says we will be covering the first seven chapters of Smith, Eggen, and St. Andre's "Transition to Advanced...
32. ### Quantum Intro to Quantum Electrodynamics

Hi folks, Electricity and magnetism have always been my favorite subjects, and I am just getting to learn the basics of quantum theory and it is absolutely terrific going. I was always fascinated by the story of Feynman, Schwinger, and Tomonaga tackling QED from the books Genius by James Gleick...
33. ### Would someone mind checking my proof? Intro Real Analysis

Here is my solution. I used mathjax to type it up in Overleaf. I feel like it makes sense, but I also have a feeling I might have "jumped the gun" with my logic. If it is correct, I would appreciate feedback on how to improve it. Thanks!
34. ### I Intro to Symbolic Logic: Replacement Rules

Basically the problem starts with these given premises: 1. ~ (A ∨ (B⊃T)) 2. (A ⋅ C) ∨ (W ⊃ ~D) 3. ~(P ∨ T) ⊃ D 4. ~P ≡ ~(T ⋅ S) And from these premises, I must prove ∴ ~W. This is what I have done so far: 5. (~P ⊃ ~(T ⋅ S)) ⋅ (~(T ⋅ S) ⊃ ~P) B.E. 4 6. ~P ⊃ ~(T ⋅ S)...
35. ### I Exploring Entropy in Intro to Statistical Physics by Huang

Hi, I am currently reading Introduction to statistical physics by Huang. In the section of entropy, it reads But what if I choose ##R-P## as a closed cycle? Then in a similar process, I should have ##\int_{R} \frac {dQ} {T} \leq \int_{P} \frac {dQ} {T}## and ##S \left ( B \right ) - S \left (...
36. ### Other Intro Logic Books (differences between Peter Smith, J.J. Smith and P.Teller)

I want to get started with FOL and decided to get through some very basic book first. Currently looking at: A Modern Formal Logic Primer - Teller An Introduction to Formal Logic - P.Smith Logic: The Laws of Truth - J.J. Smith These 3 books are frequently recommended I just don't know which...
37. ### Quantum Intro to QFT notes/texts (minimal "external guidance")

Hi everyone, My university has completely scrapped an undergrad Intro to QFT course and I am essentially left with no choice but to do self-study with no (worst-case scenario) external guidance. Are there notes or texts that can be used for such a purpose? Would be a nice bonus if there's a...

39. ### Intro Physics Calculus based intro physics textbook recommendations?

Hi, I'm a first year physics student who still hasn't found a textbook for his class. Our professor mentioned that any calculus based book is okay, but I can't seem to find anything! He suggested Halliday and Resnick's Fundamentals of Physics (extended edition), and although it covers the...

41. ### Intro Real Analysis: Closed and Open sets Of R. Help with Problem

For the set A: Note that if n is odd, then ## A = \{ -1 + \frac {2} {n} : \text{n is an odd integer} \} ## . If n is even, A = ## \{1 + ~ \frac {2} {n} : \text{ n is an even integer} \} ## . By a previous exercise, we know that ## \frac {1} {n} ## -> 0. Let ## A_1 ## be the sequence when n...
42. ### Thoughts on using the Scratch language as an intro to programming

I recently encountered the Scratch programming language. I wonder what people think of it considering some notable (IMHO) shortfalls. I do not like the way it handles comments, the lack of returned values from "functions", and some other aspects that I think should be basic. But it does seem to...
43. ### Relativity Textbook for "Intro" course in GR

I was just looking for recommendations for textbooks for an Undergraduate (Senior) Level course in General Relativity. I want to prepare for this "Intro" GR course i'll be taking in January by self-learning what i can beforehand in summer, does anyone have any good, first hand recommendations...

45. ### MHB Intro to Logic (prove sequents)

I am stuck on these questions and don't really know how to start/solve them. prove the following sequent: 1. $(\exists x) Fx \to (\forall x) Gx \vdash (\exists x)(Fx \to (\forall x)Gx)$ 2. $(\forall x)(Fx \to (\forall y)\neg Fy) \vdash \neg(\exists x)Fx$ 3. \$(\exists x)Fx, (\forall x)(Fx \; à...
46. ### Schools Comparing AP Physics C to College Intro Physics Courses

To the people who took AP Physics C in high school and then took the introductory Calc-based physics sequence in college; how does Physics C compare to the Intro Sequence?
47. ### I Griffiths: Intro To Quantum Example 4.3 clarification , <Sx> =

Hello, In Griffiths Intro To Quantum (second edition) example 4.3 page 180 ... Calculating the expectation of <Sx>, equation 4.164. I'm sure I am wrong, but it seems like after using Euler's for the e^i terms there should be 2cos(yB0t)'s terms. I agree the sin's cancel (After using Euler)...
48. ### Courses Taking Intro to Differential Equations after a break from school

I'm currently an undergrad student who had to take a break from school for over a year and its been around 3 or 4 years since I took Calc I - Calc III and Linear Algebra. I'm debating on taking a introduction to differential equations course as an elective that starts in a couple weeks when I...
49. A

### What are the top resources for learning about physics and science on PF?

Hello, everyone! My name is Akshay. I like to read Physics articles, especially regarding Relativity, Quantum Mechanics and Computing. I hope to be able to contribute to the forum in a meaningful way.
50. ### Intro to thermal Physics - D. V. Schroeder -Entropy question

Hey guys, so I am reading this book and on pages 89-90, the author says: "Increasing temperature correspond to a decreasing slope on Entropy vs Energy graph", then a sample graph is provided, and both in that graph and in the numerical analysis given in page 87 the slope is observed to be an...