Hard Definition and 1000 Threads

Homework Statement What is the next number in the following series? 1 2 12 48 216 936 4104 17928 78408 342792 ____________ Homework Equations I haven't any ideaThe Attempt at a Solution power's of two, powers of three, prime numbers. I am beat it can be found on this test...

Homework Statement The hard drives of many desktop computers spin at a maximum rate of 7200 rpm. If the diameter of the spinning disk in the harddrive is 3.51 cm, calculate the magnitude of the centripetal acceleration on the outside radius of the disk. Homework Equations ac=v2/r...

Before the days of fast internet access, I eagerly made copies of interesting technical articles. I even bound them up using "stab binding". However, the way they piled up was a depressing reminder of all the knowledge that I was never going to take time to investigate. Now that the internet...

in terms of what buying what is the dereference between hard and soft iron? i know an iron core is good but what about cast iron?

Homework Statement I have attached the question Homework Equations The Attempt at a Solution so the first thing I did was find the frequency = 120 Hz The next thing I did was find the circumference = 0.2796 m (from pi*d) Now I know that the answer is no. magnets per disk *...

Homework Statement A very light rigid rod with a length of 0.062 m extends straight out from one end of a metre stick. The combination is suspended from a pivot at the upper end of the rod as shown in the following figure. The combination is then pulled out by a small angle and released...

Homework Statement For this problem assume that the 365 dates of the year are equally likely as birthdays. b)Find the probability that in a group of n people, at least two have the same birthday. Homework Equations The Attempt at a Solution Well I am not really sure what...

My question is pretty much what i wrote in the title, I'm wondering how hard a phd in mathematics from mit or an ivy league univ would be.

Tuberculosis pathology is hard! Hello, I'm reading tuberculosis pathology and I'm finding it hard to understand because my general poor knowledge in pathology. This is what I gathered from the reading. 1. Tubercle bacilli reach alveoli of lung and ingested by macrophages. 2. Then...

Homework Statement \int e^{3lnx} + e^{3x} dx Homework Equations The Attempt at a Solution Not sure if I should use an e substitution or if I'm forgetting some easy e rules... Any help appreciated.

Hi everyone, i'm new here. i want to know how to clone the hard drive of computer. which software is the best? i heard about norton ghost but is an alternatives? And is it possible to find a step by step procedure to do this. Than you very much 042012

[Question] Identify what, if any, bias is found in each of the following sampling scenarios. Explain your answer for each one. a) Selecting some residents of a building to participate in a survey of recycling options based on the last digit of their phone number b)Deciding whether to...

Homework Statement Find the arc length of the ellipse or deformed circle. r^2=x^2+(y/β)^2 r=radius β=dilation constant k="random" constant Homework Equations The Attempt at a Solution I suspect it's impossible but I can't prove that. After working it out I got stuck with these...

A question has arisen (not homework) showing two pulley systems and a box being pulled up with a man pulling each. The question asks who has to pull hardest. On one of them (A) the shafts (supporting the rope) are smaller whilst on the other (B) they are larger. The correct answer is that the...

"I wish I hadn't worked so hard." Top Five Regrets of the Dying http://www.guardian.co.uk/lifeandstyle/2012/feb/01/top-five-regrets-of-the-dying

I'm sure there are some of you (most, if not) who've experienced this, but mine's really bad. When I have classes for the next day, I could not sleep the night before because I'm thinking too much, ironically it's about being not able to sleep. During the days where I have no classes, I seem...

Please see the attachment. Under the given range of parameters the integral converges, but I can't find a closed form solution. It seems one has to integrate very special functions other than simple Beta, Gamma, Error functions etc..

Hi everyone. I'm a senior undergrad and about to obtain a bachelors in physics from a top US university. I specialized in solid state physics and am doing my undergrad honors thesis in graphene synthesis and characterization. I want to eventually work in the semiconductor industry or with...

Title says it all. I was debating this with some friends that if I came into a nice hunk of funds, just how hard would it be to finance a two man ship to go to Mars?

I have read countless articles, threads, discussions, you name it, about engineering, because I have always been back on forth on whether I will succeed at it or not. I have been going to a state university for two years, and am starting at the technical institute this summer. Deciding between...

Homework Statement Hello, i encounter a conceptual probability problem that I think i have come into confusio. The situation is - There are 3 Blue ball and 1 Red ball in a bag (BBBR), while there are 4 Green balls in another bag (GGGG) If one of the balls is taken from bag A to bag B...

I have read my text and watched youtube videos but this just won't register in my brain. Does anyone have a much simpler way to explain it or know of another source that can help. Specifically, how would one use it to figure out the direction a current is going given a variety of different...

It seems like everyone I know believes that probability is much easier than Calc, but I believe that's a subjective point of view. I know that Calculus has various levels (i.e. I,II,III), but is it really all that much more difficult than probability? How many different 'levels' of probability...

http://im16.gulfup.com/2012-03-07/1331125411751.png I know the answer is (E) , but HOW ?

I am trying to calculate the covariant derivative of the Ricci Tensor the way Einstein did it, but I keep coming up with \nabla_{μ}R_{αβ}=\frac{∂}{∂x^{μ}}R_{αβ}-2\Gamma^{α}_{μ\gamma}R_{αβ} or \nabla_{μ}R_{αβ}=\frac{∂}{∂x^{μ}}R_{αβ}-\Gamma^{α}_{μ\gamma}R_{αβ}-\Gamma^{β}_{μ\gamma}R_{αβ}...

I am trying to calculate the covariant derivative of the Ricci Tensor the way Einstein did it, but I keep coming up with \nabla_{μ}R_{αβ}=\frac{∂}{∂x^{μ}}R_{αβ}-2\Gamma^{α}_{μ\gamma}R_{αβ} or \nabla_{μ}R_{αβ}=\frac{∂}{∂x^{μ}}R_{αβ}-\Gamma^{α}_{μ\gamma}R_{αβ}-\Gamma^{β}_{μ\gamma}R_{αβ}...

My laptop is equipped with hard drive shock protection. If I am watching a movie and the accelerometer senses a perturbation (me shaking the computer) the image is immediately frozen, but there is no interruption in the sound. Why is this the case?

Is it possible, or worth the trouble? A little background info: I'm currently a freshman at a small liberal arts college. I didn't give much thought to anything outside of the humanities when I chose to come here because I wanted to go to law school, which doesn't require any prerequisites. I...

thanks to read my message after transfer my document and plug out my external hard " my passport 3.0 500 g.b " all data delete , please help me

\[ \int \sin^{12}(7x) \ \cos^{3}(7x) \ dx \] Ho do I solve this Integral? What can I substitute??

Homework Statement Please refer to the figures. (The first one is multiple-choice, the latter is structured). Homework Equations For the first problem: u = √(2gH) x = uxsinθt + \frac{1}{2}gsinθt2 uycosθt = \frac{1}{2}gcosθt2 and maybe others u = initial velocity x = x-displacement...

How hard is it to switch fields in science? For example, say you do your Ph.D. in an area of theoretical physics and are very successful, but cannot find further funding at some point (can't land a postdoc in your chosen field, no professorship offers, denied tenure, etc.). How difficult would...

Hi, I am a sophomore and I recently dropped Graduate Complex Analysis. I was just missing something. The solutions to the questions on the problem set were not capable of being formed by me. This being said, I am wondering if it is still possible for me to attend graduate school for...

Homework Statement Homework Equations The Attempt at a Solution V=20 S=6 E=2 H=20/12 (from V=SEH?) \frac{dS}{dt}=-.2 <--- + OR -? \frac{dE}{dt}=.3 <--- + OR -? V=SEH Product rule for 3 variables: \frac{dV}{dt}=SE\frac{dH}{dt}+EH\frac{dS}{dt}+SH \frac{dE}{dt}...

Hi guys I'm wondering how shall I solve this primitive/integral \int\frac{\cos^3 x}{x^6+1}dx I really don't know how to start... which substitution shall I take or if I shall solve it by parts... Any hints or tips will be very appreciated Thanks in advance

I decided from the start of this year i would work harder and study more maths not that I am bad I am actually very good for a 14 year old turning 15 because i want to be a theoretical physicist one better than einstein but no matter how hard or how long i study maths or work on it it always...

Now you're all mostly physics heads on this forum, so it's important to consider than I understand about 1/75th of what is said on this forum. I love physics, I find it fascinating - but I went to this consultation meeting thing and I was basically told that unless I'm a maths freak I'll...

Scientifically, we are just a chemical process on the the surface of a giant rock. The only reason why we do what we do is because "It feels nice". All those long hours at the university and studying. What does it ultimately accomplish? This video explains further http://youtu.be/QK0rsh7WeYY...

Hello all, Firstly, sorry for the long post, I was just wondering if someone is in a similar position and would like to hear their thoughts and how they deal with certain things. If it is too long, just skip to the questions I have under each paragraph. I was never spending much time...

##\newcommand{\dmu}{\ \mathrm{d}\mu}## I'm using Friedman to try to learn some integration theory. I got the impression that all books start by defining integrals of simple functions in the same way, and then there are several different ways to generalize the definition to more interesting...

I don't really have a background in EE, I have a background in Computer Engineering Technology. It's a lot less theoretical and more of a hands on degree. I'm just wondering if I'll have a hard time in graduate level courses in EE. I have a strong programming background, know my way around...

x = 3^6 * 2^12 y = 3^8 * 2^8 x^x * y^y = z^z for some integer z Find z. I took the log of both sides, but don't know what to do next (I'm not even sure taking log of both sides will produce anything).

Taking calculus and have hard time understanding the textbook. Help please. My textbook is called Calculus:One Variable by Salas (10th Edition) I'm at University of Toronto in Canada. My course is named MAT137. A lot of students in my course don't read the textbook. They only do exercises...

Hard Grade 12 Trig. Questions :( Homework Statement http://img831.imageshack.us/img831/8389/daumequation13263429629.png Homework Equations No equations are required. The Attempt at a Solution http://img845.imageshack.us/img845/9519/34851996.png...

I have a laptop and I'm running Windows 7. I recently downloaded AutoCAD and some other CAD software and I needed extra storage space on my laptop, so I bought an external hard drive. I was wondering if there was any way I could reinstall any programs onto the external HD to clear up some...

Hiya! Long time registrant, have not used these forums is years though... Anyhow, the problem I have is that I need to collect data from a very large number of images that are essentially horizontal lines on a page. I've attached a sample here, which has been processed to find the edges of...

Hi, I'm currently trying to work through a problem about calculating the most likely time for a hard disk to fail: Hard disks fail with a probability per unit time: \alpha (t) = \alpha _0 t where \alpha_0 = 0.5 years. I know that the answer is t_{modal} = \frac{1}{\sqrt{\alpha_0}}, but am...

Homework Statement An RLC circuits consists of R1 a 10-ohm resistor, R2 a resistor that takes 50 W, C1 a capacitor with 5-ohm reactance, and L1 an inductor that takes 100 var. Find the value of R1, R2, and Xl (inductive reactance).Homework Equations P = (I^2)R Xc = 1/(2∏fC) Xl = 2∏fL Z =...

Hi all. I'm looking for a paper that I've seen referenced in a couple of articles I've been reading. The paper is O. M. Kiselev, Determination of gas-bubble shape in axisymmetric flow of fluid, Zh. Prikl. Mekhan. Tekh. Fiz., No. 3 (1963). The English name of the journal is Journal of...

Homework Statement We know that y = Aex is the solution to the initial value problem dy/dx = y; y(0) = A. This can be shown by solving the equation directly. The goal of this problem is to reach the same conclusion using power series. Method: Let y be a solution to the initial value...