Hard Definition and 1000 Threads

I'm having quite a bit of difficulty in my college's intro honors, calc-based physics class. I want to find some good resources, either online or text, to assist with learning the material. The issue I'm having is that most resources I find are either not in depth enough, or they're just as...

Homework Statement Two blocks of mass m1 = 3.00 kg and m2 = 6.00 kg are connected by a massless string that passes over a frictionless pulley (see the figure below). The inclines are frictionless. Image - https://www.webassign.net/serpse9/5-p-049.gif The inclined plane is shaped like a...

i designed a cone drill bit with right hand thread to give friction and grab inside to give pulling force. my question is can this type of cone drill bit drill hard rock formations like normal tricone drill bits with teeth or the cone drill bit will be weak to penetrate hard rock formations .

im trying to become an award winning physicist (I know, I am ready for the grind, I am 15 and ready to start) how hard is it to first get a job in this area right out of college after a phd? any way to make 70-80k and go up to make 6-figure salaries in research for the government or in a lab...

So, I've been trying to study Mechanics in my spare time - about an hour or two every day - for over two years now. I'm up at 4:00 am most mornings studying before work. Despite being able to speak French, Italian and Irish fluently, holding a few Masters Degrees, and being a teacher myself, I...

Proposed: How can we prove $(1)?$ $$\int_{0}^{\infty}\mathrm dx{\sin^2\left({a\over x}\right)\over (4a^2+x^2)^2}={\pi\over (4a)^3}\tag1$$

..in a taught masters (UK). My undergrad project was a literature review on general relativity The topic of my project this summer (3 months) will be modified theories of gravity & cosmology. How do you go about doing some original work at this level? - would the first step be to identify a...

<Moderator's note: Moved from a technical forum and thus no template.> where a, b, c, d and n, all are positive integers. Find the value of 'c'. ------------------------------- I don't really have a good approach for this one. I just made a substitution u = sinx + cosx I couldn't clear up...

Hello, I'll try and keep it short and sweet. I'm 21, female and left school at 17 due to depression caused by the death of a loved. I did not finish high school. I was bright in English and History related subjects and always excelled but didn't take notice of maths or science until recent...

Homework Statement In frame S particle 1 is at rest and particle 2 is moving to the right with velocity u. Now consider a frame S 0 which, relative to S, is moving to the right with velocity v. Determine the value of v such that the two particles appear in S' to be approaching each other with...

Ok, so it has been about 4 years since i have had physics for scientists and engineers. I am a full time mechanical and areospace student. I just started dynamics class and right off the bat, i ran into an equation that i am not sure how to infer. It is from our rectilinear example: d^2x/dt^2 =...

I am currently working on writing an ML program that predicts star formation rate of a galaxy given the magnitude of filtered color bands (ugriz). I have a simulated data which contains these info to train on but if I want to use this on an observable galaxy, I'd need to physically obtain the...

.. and done by a Chinese author: Liu Cixin. Here are some reviews: https://www.goodreads.com/book/show/20518872-the-three-body-problem. So: What do you know about the general three-body problem and would you like a story set in a solar system with three suns?

Hi guys. My question is about science. If scientists, or people that want to became scientists, have to choose and only one field of science, like physics, chemistry, biology, math, etc...there isn't the risk of limitate themselves? I mean, you know, every science field is very wide, and time is...

Hello. Is it hard to achieve a PhD in, for example, physics? What do you have to do/study beforehand, like in school? Is a PhD like a first published paper/research? How do you achieve a PhD is things like physics and mathematics, which are so theoretical? If I want a PhD in physics or...

Homework Statement I'm given the integral show in the adjunct picture, in the same one there is my attempt at a solution. Homework Equations x = r.cos(Θ) y = r.sin(Θ) dA = r.dr.dΘ The Attempt at a Solution [/B] I tried to do it in polar coordinates, so I substituted x=r.cos(Θ) y=r.sin(Θ) in...

Hi, I have been upset lately due to getting a low mark in one of the most important courses in my life. I am a fourth year nuclear engineering student. I have been an average student since high school. my uni gpa is average too. I don't know if it's the way I study is what I am doing wrong or...

Homework Statement Homework Equations [/B] I came over these Equations when I was Reading an article. I tried to replicate the results by differentiating Equation 9 w.r.t time. However I could not do it. Just to be sure. The growth of a variable is Equal to the time derivative of the same...

When the car is accelerating let's assume the force on it is ma. In order to stop this force we have to apply the brakes which apply a force in the opposite direction. But this force should not exceed ma. It is because the additional force will act on the tyres and create an additional...

0 down vote favorite There is a lot of material discussing the rotational speed of the magnetic disk in HDD but not about the rotational speed of actuator arm. What are the typical actuation speeds of the actuator in HDD? This information will be used in the design of a fast shutter system...

What is the situation for my hard drive now? Can I fix it with a software? Should I change it? The PC is working with no problem? What should I do now? Should I change the hard drive in the service? S.M.A.R.T status is bad. There was nothing a few days ago. I cannot understand how this has...

I have some diamond powder and was wondering how I can turn it back into its hard stone form? What can I do. I'm a hobbyist chemsit/physicist. I just need some help from more knowledge people

First,a bit of context... I've just finished high school in Malaysia, and I'm a bit torn on which country I should go to further my studies. I have a deep interest in theoretical physics and I'm hoping I can get a physics degree. My current first choice is to attend a community college in the...

Homework Statement (ignore the suggested problems for test 3.) If for whatever reason the image doesn't load the given's are that: The area is 25pi(.125m)^2 (A circular coil with 25 turns and a radius of 12.5cm.) The magnetic field varies with time and is...

It seems that most recently published analysis textbooks are written from a more abstract perspective, e.g., dealing with functions on general metric spaces or with spaces of functions. However, often solving a problem requires some "get your hands dirty" classical or "hard" analysis -- for...

Used as a boat buffer.

So far in my reading of SR, we explore various consequences of c being a constant in a vacuum and frame invariant, etc. At what point in a physics education do you learn why a universal speed limit is necessary at all? Is that the sort of thing that is revealed in an intro to GR course? Or is...

Is that "normal" for a machine running Windows 10? I have a 120GB hard drive and 55.2GB is being used for System & Reserved. Seems high.

I've been working for about a year now as an engineer. I find myself thinking that the amount of mental effort that I have to put into my job relative to what I'm paid sucks. By the way, my pay is competitive for my position and years of experience. However, I see that the senior engineers are...

In the standing broad jump, one squats and then pushes off with the legs to see how far one can jump. Suppose the extension of the legs from the crouch position is 0.600 m and the acceleration achieved from this position is 1.25 times the acceleration due to gravity, g . How far can they jump...

Homework Statement I'm fine with the first part. Part b) is causing me trouble http://imgur.com/xA9CG5G Homework EquationsThe Attempt at a Solution I tried subbing in the solution y1 into the given equation, but I'm not sure how to differentiate this, i thought of using integration by parts...

According to the Lorentz transformations, in the absence of gravity, the relations between coordinates of a primed system to those of a unprimed system are $$x'^{\ \alpha} = \Lambda^{\alpha}{}_{\beta}x^{\beta}$$ For the Lorentz invariance to be satisfied we must have...

Hey guys, I'm looking for some nice new physics challenges similar to physics.harvard.edu Problem of the Week or the 2 star and above problems in Morin's Intro to Classical Mechanics (also Feynman problems). Where else can I find such problems? Or does anyone know of a few that they could share?

I have been trying to teach myself quantum optics for some time. Up to now, I have often looked at certain types of integrals -- the ones that have operators within them -- without going into too much detail, just trying to get the general purport and moving ahead, only to get mired in some...

Hello. I am working on planning to build a small pnumatic tricycle. I got far in my calculations, but not quite finished because I am stuck. If someone could check my math, that'd be great, but my problem starts at the second line. ______________________________________________ 1. Let's say...

Did you notice MWI assumes the brain is classical and when we watched the double slit, "that observer will "split" as well--one version of him for each way the double slit experiment came out." MWI assumes the so called easy problems only. Before I proceed. Please read short paragraph of...

And I am not talking about celebrities such as someone like Stephen Hawking, who are famous scientists. I am talking about those that are people you'd never expect having an interest in mathematics, chemistry, physics, etc.

Is it possible to learn relap5 without a teacher ?

Hi all. I've been working on this for two days and I feel embarrassed that I haven't been able to figure it out. I'm dealing with the following cocurrent diffusion situation between an aqueous and gaseous flow moving at the same velocity: X% of the liquid is removed and replaced with fresh...

Homework Statement Question 1. A triangular prism of mass M is placed one side on a frictionless horizontal plane as shown in Fig. 1. The other two sides are inclined with respect to the plane at angles a1 and a2 respectively. Two blocks of masses m1 and m2, connected by an...

Hello, Not sure really where to ask this but I couldn't find a good answer so why not a physics forum, because well this involves physics. I just got a gopro for my fpv drone and I am wondering what type of case to get for it, either a plastic or silicone one. If I am going 30+ mph and smack...

I need someone to bring me back to reality because I may have disillusioned myself. I thought that it should not be too difficult to get a temporal job, graduate programme etc. applying from Europe. Yet I have so much trouble finding ads with visa sponsorship. I also start to think that my...

I am currently studying C Hammond's "Basics of Crystallography and Diffraction" (third ed.). In the first chapter ,concerning hard sphere model, I have found the following statement: There are, in fact, no examples of elements with this structure because, as the model building shows,the atoms...

Given that 1.34Tbit of information can fit on a square inch of average hard drive surface, how many 400 KB files could be written on a square millimeter? I did the math and came up with about 634. This seems unbelievably high and I wonder if someone would have time to check it. I kind of need...

I have been using Nebulosity to stack multiple images. Doing just that was not beyond me and lo! the noise level drops impressively. I then needed to get the colours to work. De-mosaicing (disgusting word) is necessary to produce a .fit file from .dng. Using the pre-sets in the dialogue (a 3x3...

I had a drive that every few minutes makes a buzzing sound. Here's what SMART is telling me. ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x000b 071 071 016 Pre-fail Always - 61213753 2...

Homework Statement Force F = const is applied to H.O. initially at rest with mass m, freq w0, damping T. Find x(t). Find work as function of time. Homework Equations mx'' + Tx' + kx = F for F= Constant The Attempt at a Solution First obtain complimentary solution for free H.O. which I get...

Homework Statement An object of mass m starts from rest and slides a distance d down a frictionless incline of angle (theata). While sliding, it contacts an unstressed spring of negligible mass as shown in the Figure below. The object slides an additional distance x as it is brought momentarily...

I used to like math when I was in high school. Calculus (integration and derivatives) seem intuitive to me and made me understand math so much better. Now I'm currently in university majoring in civil engineering taking Calc III and I feel overwhelmed by everything taught in class. No matter...

Homework Statement Homework Equations Kirchhoff;s first and second law, V=IR The Attempt at a Solution Tried the question as follows: V= 24/(2+6+4) = 24/12 = 2V (pd from top cell) then did 2=4 I3 therefore I3 = 0.5A and then 2 = 6I2 I2 = 0.33A and I1 = 0.5+0.33... =0.83A?