Strange Definition and 549 Threads

I have a few of these to do so would appretiate if someone could explain this to me as i am stumped. Find in terms of k a solution to the equations, x+y+kz=4 x-2y-z=1 kx+7y+5z=10 For what values of k is this solution not valid? Man thanks in advance for any help given.

Homework Statement "K" is the time derivative of acceleration. Assume initial conditions of Ao, Vo, and Do.("o"=initial). Find: a(t): v(t): d(t): Show that: af^2=ao^2+2J(Vf-Vo) Homework Equations I'm honestly lost on this one..I don't know where to start. I could probably...

Homework Statement Einstein's theory of general relativity is relativistic model of gravity. "Relativistic" means it involves the speed of light, c; "gravity" means it involves Newton's constant, G. Use dimensional analysis to derive a formula for the surface area, A, of a black hole of mass...

Homework Statement Einstein's theory of general relativity is relativistic model of gravity. "Relativistic" means it involves the speed of light, c; "gravity" means it involves Newton's constant, G. Use dimensional analysis to derive a formula for the surface area, A, of a black hole of mass...

Is it possible to launch the satellite into orbit with inclination less than of latitude of the launch site? Can you please explain to me using some formulas.

Isn't this strange! Hello, Sometime ago I realized sth strange for most of the polynomials; For example, [tex]y=x^2[/itex] if we take f(x+d) as a multiple of f(x), I mean: f(2)/f(1) = 4 hence 4*f(1) = f(2) so 4 is a multiple of f(1). Now; [tex](x+d)^2/x^2[/itex] as x...

So, I've noticed that when I freeze ice cubes these strange icicles appear on the top of the ice. I took a picture, included as an attachment. Not really sure how something like this forms. Please no speculation.

Hello, I've been writing a program to communicate with an embedded system via rs485 The protocol in use utilizes stick parity, where stick parity is defined as the first byte (which corresponds to the address of the device) having its parity bit set to 1, and the rest of a packet have its...

I am really sorry for posting this general topic here :redface:; I couldn't find any other place. So, here's what I observered: The rate at which new people join this forum is exceptionally high during this time of the year. So, just wondering why?

I have an ADSL connection to my PC. I bought an ADSL WIFI antenna box so I can receive the high speed internet network on my notebook in the other room or backyard of my house. It works OK, I can even completely turn off my desktop PC and just connet the WIFI box - antenna to power supply and...

Hello people, I'm reading one technical article about PLL and I have found this: In this second part, we will focus on a detailed examination of two critical specifications associated with PLLs: phase noise and reference spurs. I don't know what reference spurs means? I can conclude from...

Don't know if this is the right place for such a question... I plotted these graphs based on data taken from the black box of a plane: http://www.planetmobile.it/jumpjack/immagini/volo93-grafici.GIF I can't fully understand these data: looks like while the plane was falling down, it was...

Let me start by saying this is just a problem posed to me. I had this prof before so some people thought I might could see what he was thinking. OK here is the problem two in phase sources of waves are separated by a distance of 4.00m these sources produce identical waves that have a wave...

I've been listening to a lot of David Bowie lately. Particularly stuff from his early 80s "Man Who Fell to Earth" phase. Looking back at the diversity of his discography over the years, you can't help but notice that he never ceases to reinvent himself. You get the feeling that he becomes...

Homework Statement This is part of a problem for a nonlinear diff class... But it's the basic stuff that's tripping me up. Find all the max/min and concavity for v(x) = -cos(x)-Lx+1,\ \ \ 0<L<1 The Attempt at a Solution Here's what I do: v'(x) = sin(x)-L v''(x)=cos(x) Set the first...

For all those math majors out there, is it just me or do people (non-math/physics majors) give you a strange look when you say that you're a math major? Just recently I changed my major from Biology to Math. Whenever someone asks me how the Bio major is treating me, I reply saying I switched to...

This is a problem and i show you my work, what i don't understad is how to differentiate things like: d(cos(t)) / dp is all i have done so far madness? or where iam i doing wrong? (i did not got the answer myself)

I am a first year Materials Science & Engineering major at UCLA, and was recently offered (sort of) admittance into Stanford if I wanted to transfer. What do you guys think? Would this be a bad move? I have some of my own ideas but I would like to hear from you, thanks.

Hi all, I was hoping for a little advice and some insight on these pictures I took. Here is the first (orig_small1.jpg): And the Second after I realized and waited for a break in the traffic (orig_small2.jpg): I was on the Skyway Bridge in the passenger seat driving from St. Pete...

Take n/(n+1)-n/(n+2) as n->infinity results in the limit 0 But take the same equation convert it to n/(n+1)/(n+2) as n-> infinity results in the limit 1. What is going on? The expression is the same yet you get two different limits. Something is wrong.

Hello, can anybody help me out with the following (IMO) strange reaction: HE-4(N,P)H,SIG I'm looking for the thermal neutron reactions on He-4, and according to this site: http://www3.nndc.bnl.gov/exfor7/endf00.htm (enter target He-4, reaction n) the above reaction has a...

For as long as I can remember I have had this sensation (and before you ask, I am not smoking anything). The feeling only occurs when I am in bed and starting to fall asleep, the only way to describe it is a strange feeling of big and small at the same time. It’s like a very tiny dust particle...

We have \int \frac{d^3 \texbf{q}}{(2 \pi)^3} \frac {e^{i \texbf{q} \dot \texbf{r}}} {q^2 + K^2} = \frac {e^{-Kr}} {4 \pi r} How do we get from the left hand side to the right hand side? I've tried regular Fourier transform of the function under the complex exponential I think that gives...

I was copying notes in class down, now that class just ended, I was reading over the notes, and I saw this line that went from... THIS: \frac{x-y}{2x} = \frac{dy}{dx} To THIS: \frac{1}{2}(1-\frac{y}{x}) = \frac{dy}{dx} But I'm wondering... wouldn't It be this...

The World's Most Expensive Coffee is From Beans Cycled Through an Indonesian Monkey's Digestive System-Truth! Summary of eRumor: Kopi Luwak is a rare and gourmet coffee from Indonesia that is made from beans passed through the digestive system of monkeys. The Truth...

Hello, I was curious about any thoughts any of you might have concerning an interesting result I found today. While I was annealing a 32 cm wire of nitinol at about 300 C, which for its diameter is about 1 amp, I noticed that when the wire was made less tense, it moved up and down...

A strange function... Last night I was faced with a strange function & I couldn't figure out the equation of the function hence I thought I can get some help from the math experts over here... The function passes through these cordinates: (3,1) (4,1) (5,2) (6,2) (7,3) (8,3)...

A small block of mass m is on a horizontal frictionless surface as it travels around the inside of a hoop of radius R. The coefficient of friction between the block and the wall is mu; therefore, the speed v of the block decreases. In terms of m, R, mu, and v, find expressions for: a. the...

Forgive me if this ends up not being a physics question, but I've noticed that when you turn on the burners (electric) they make a sound that almost sounds like they're stretching, but not a continuous sound, more like a series of closely spaced ticks. This sound seems to increase and decrease...

Well, strange in my opinion, hah. This is actually for my differential equations class...but I figure it's stuff that I should've already learned. Now for something that we are doing, the number of roots are important. So upon factoring something like (m^4 - 2m^2), it goes to m^2(m^2 -...

Can someone tell me how to do this problem? I Don't even know where to begin.

Now here is a strange one from way back that I heard recently. Midnight At The Oasis

I decided to numerically calculated pi using MATLAb and running a for loop. When I make the steps too small I get absurd quantities for pi. Here see for yourself. When I make the interval higher then about 1e10 i get errors, but 1e6 works ok. Why would this be? Thanks <code> clc...

Hello! I'm just doing the Problems of Chapter 1 of Sakurai: Modern Quantum Mechanics. On page 60, problem 2 he writes: "Suppose a 2x2 matrix X, (not necessary Hermitian, nor unitary) is written as X = a_0 + \mathbf{\sigma \cdot a} , where a_0 and a_{1,2,3} are numbers." which confuses...

1. Does light(photons) have 0 mass or infinite?(b/c it its mass would be zero, it would take no energy to slow it down, meaning, it wouldn't be traveling, unless it has infinite mass which means that it can't be slowed down even a bit but that contradicts the theory that it does have 0 mass)...

The strange meaning of .."complex delta".. Let's suppose we introduce the function.. \delta (a+ix)=f(x) a a real number.. then following the representation.. \frac{sin (Nx)}{x} f(x) is oo elsewhere...except for pure complex numbers. f(x)(2\pi) =\int_{-\infty}^{\infty}du...

According to Hardy's book "divergent series" the sum: g(x)=1/2+cos(x)+cos(2x)+cos(3x)+... has sum equal to 0 (¡¡¡¡¡¡) then if we integrate in the sense: \int_{0}^{b}f(x)\sum_{n=0}^{\infty}cos(nx) dx \rightarrow (-1/2)\int_{0}^{b}f(x)dx :rolleyes: :rolleyes: since the sum...

Just to cause confusion. :smile: Actually, it's been a really strange couple of weeks. Two weeks ago, all our company's employees working on a contract were supposed to go to a mandatory meeting in our company's district office. At the last minute, it's canceled. Two days later, we find...

Hi all ! I've looked at a strange video on the net of an obscure compagnie that pretend to create electricity (5 times more energy than it consume). This video was very entertaining, I laughed a lot. But, there was something special that intrigate me... The pseudo-scientist take a permanent...

Well Strange to me at least, A man wants to build a patio on his house in the shape of an isosceles triangle. He wants to build the side walls out of pink planks, but he has only 600 yards worth of planks. Find the dimensions of the largest area he can build if he's using the side of his...

I have been wondering something. Assuming strange quark stars exist (and I know that this is still too early to call), is it possible that a black hole might just be an overgrown quark star that has gone over the required mass (say from feeding on a nearby star or a collision)? Is there any...

The question is a volume of 2.2m^3 of air at inital conditions of 1.2bar and 303K undergoes the following process to complete a cycle : i)isothermal compresssion from state 1 through a volumetric compression ration of 6 to state 2 ii) isobaric expansion from state 2 back to the initial...

These are machines that I just learned about while I was bored. So, i will now ask about what looks like a triangular toothpick ion engine. So these lifters are really strange, I don't know how they work, http://www.americanantigravity.com/articles/256/1/Lifter-Plans here they are...

Ok, so we all know the following... Elementary quantum mechanics is constructed by postulating the canonical commutation relation (CCR) between the coordinate of a particle and its conjugate momentum. Quantum Field Theory, on the other hand, is constructed by postulating the exitence of a...

A few of my friends and I have been trying to integrate/derive the following: f(x) = x^x without success. I'm not sure if it can be done conventionally, but I was wondering if anyone had any thoughts on this one. Thanks.

Mars is likely to be the first planet that we might decide to terraforum. Problems with Mars is its low atmosphere and cold temperatures. I have seen many strange concepts for terraforuming Mars. Like nuking Mars (not a good idea) to building factories to pump out green house gases...

I've been having these dreams lately, where I'm at the final period of my semester and I've incredulously found that I've missed out on a class that I've registered for...the entire semester! Sometimes there are variations in the severity, e.g. it seems that I've missed out on an exam, or have...

I'm in AP Calculuc and was given a homework package, which is an old university introductory calculus exam. There is one particular question with which I'm having a terrible time. It is known that f(0)=5 and the tangent line to the graph of f(x) at (0,5) is y=5+3x. It is also known that...

"strange" sums... Let be the next 2 sums in the form: f(x)+f(x+1)+f(x+2)+... (1) and f(x)+f(2x)+f(3x)+... (2) how would you calculate them?..well i used a "non-rigorous" but i think correct method to derive their sums..let be the infinitesimal generator D=d/dx...

Did you know that the word 'gullible' does not appear in the dictionary?