Absolute Definition and 1000 Threads

Homework Statement An experiment to measure density, d, of a cylindrical object uses the equation d=m/(pir^2l) where m=mass=0.029 +-.005kg r=radius=8.2 +-.1mm l-length=15.4+- .1 What is the absolute uncertainty of the calculated value of the density? Homework Equations above The Attempt...

Homework Statement http://imgur.com/RlIdmFh http://imgur.com/3dnLK3m Homework Equations |x| = -x? The Attempt at a Solution I'm trying to make sense of this definition in my book because they are trying to prove the triangle inequality(second link), yet it keeps saying that the absolute value...

Specifically when doing integration problems. I know the indef integral of cosx/sinx+1 is ln(sinx+1) + C, but absvalue is not required here. I think it's because the sine fn must be >= 0 or it's undefined? What about in other cases, is there a general rule to know when to use absvalue? Thanks

If ##\sqrt{x^2} = |x|##, why ##\sqrt{16} ≠ |4|## instead of 4 (please see below image)?

How does one solve an equation with two absolute value functions as below My algebra book does not show how to solve with two abs functions. 2|4x-1| = 3|4x+2| I thought this might work.. |4x-1|/|4x+2| = 3/2 then |(4x-1)/(4x+2)| = 3/2 and solve the normal way..

Sketch the region in the plane consisting of all points (x,y) such that |x-y|+|x|-|y|<=2

So if time dilation is what's left after correcting for the optical effect and we want to know our motion through the universe. We can't use light because we have no reference point to what not being in motion is and there's lots of attempts using light which doesn't work. Why don't we just take...

In the canonical formulation of QFT (to which I've been exposed), it is always argued that only differences in energy are physically observable and so we can deal with the fact that the vacuum energy is infinite by redefining the vacuum such that its energy is zero and we subsequently measure...

As far as I understand it gravity is sensitive to absolute energies, as seen directly through Einstein's equation G_{\mu\nu}=8\pi GT_{\mu\nu} Thus the local geometry of spacetime is directly affected by the local energy density (and not just differences in energy). So whenever gravity is taken...

I know a similar question has been asked but I'm still kind of stumped. Imagine the Earth on the left and a small mass to it's right separated by some distance h. You are in the frame of reference where the Earth and the small mass are moving to your right at some speed v. So, both the Earth...

Hi! One of our professors told us once that in solving problems, always use absolute pressure in the computations. Then one time, I was solving some problems from Dr. Felder's Principles of Chemical Processes book, I often noticed that the pressures used in computations were not always in...

Can we integrate: $$\int_a^b |x| dx$$ using an antiderivative of ##|x|##, namely ##\frac{1}{2} x |x|##, instead of splitting up the integration interval? I know this is not particularly useful for integrals such as: $$\int_{-5}^5 |t^3 - 8| dt$$ However, for absolute value functions with linear...

Greetings all, I found some similar threads to this but none that answered my exact question. I am doing an REU at a school I would like to attend for graduate school, and some students there have said that in graduate school admissions, I am going to be judged relative to my peers from the...

I am using Renishaw confocal Raman microscope to do photoluminescence spectroscopy of some polymer inside microchannel. When I fix the laser power and exposure time, the absolute count of intensity will change from time to time even for the same sample. I was hoping the intensity should linearly...

Hello! (Wave) The following Runge-Kutta method is given. $$ \begin{array}{c|ccccc} \tau_1 =0 & a_{11}=0 & a_{12} = 0\\ \tau_2 =\frac{5}{2} & a_{21} = \frac{5}{2} & a_{22} = 0\\ \hline & b_1 = \frac{4}{5} & b_2 = \frac{1}{5} & \ \end{array} $$ I have to determine the order of accuracy and...

Hello! (Wave) I am looking at the following exercise.We suppose that the explicit Euler method is applied at the differential equation of second order $\left\{\begin{matrix} x''(t)+(\lambda+1)x'(t)+ \lambda x(t)=0\\ x(0)=1\\ x'(0)= \lambda-2 \end{matrix}\right.$ $$|\lambda|>>1$$ What step...

Homework Statement A force P is applied to the rod which rests on a horizontal table. The following accelerations are produced. aA= 3.6m/s2 to the right, α of the rod = 6 rad/s2 CCW. Determine the acceleration of point G and B Homework Equations aG=aA+aG/A aG=aA+[(aG/A)tangential +...

Hello In relativity, what magnitude is absolute*: temperature or entropy? *absolute = equal for all observers (= a Lorentz scalar) Thank you for your time :) Greetings!

Greetings, Do we use Absloute refractive index when finding crtical angle ? if it was two mediums ( not vacuum or air) how would i calculate the critical angle ? I mean i get confused when I find relative refractive index because sometimes i get sine inverse greater than 1 which give no...

Shyan submitted a new PF Insights post Negative absolute temperatures Continue reading the Original PF Insights Post.

Say we are talking about an ideal gas. According to ideal gas law (PV=nRT), assuming the gas is now at absolute zero, if we further decrease the pressure of the environment, while keeping the container volume constant, will the gas goes under absolute zero? I wasn't an expert in Physics so...

Homework Statement [/B]Homework Equations m1-m2[/SB]=2.5log(ι2/ι1) m-M=2.5log (d/10)2 3. The Attempt at a Solution Not sure if my approach and answers are correct Please help

how do i evaluate say a definite integral from [-3,3] of |x+1|? Any advice? I'm so confused.

Let $[a,b]$ be a closed real interval. Let $f:[a,b] \to \mathbb{C}$ be a continuous complex-valued function. Then $$\bigg|\int_{b}^{a} f(t)dt \ \bigg| \leq \int_{b}^{a} \bigg|f(t)\bigg| dt,$$ where the first integral is a complex integral, and the second integral is a definite real integral...

Is it possible to achieve absolute zero?

Hello! (Wave) We have the problem $$\left\{\begin{matrix} y'=\lambda y &, t \in [0,+\infty), \lambda \in \mathbb{C}, Re(\lambda)<0 \\ y(0)=1 & \end{matrix}\right.$$ Applying the Backward Euler method $y^{n+1}=y^n+h \lambda y^{n+1}$, we get that $y^n=\frac{1}{(1-h \lambda)^n}$. So that the...

Homework Statement A diving sphere has a mass of 150,000.0kg and an external diameter of 7.000 meters. The sphere is anchored with a cable on the bottom of an ocean, at a depth of .8000 km. The density of sea water is 1025.0kg/m3. A) What is the absolute pressure at that depth in pascals? B)...

Acting upon a vector say, so it is defined as: ##\frac{d}{d\lambda}V^{u}+\Gamma^{u}_{op}\frac{dx^{o}}{d\lambda}V^{p}=\frac{DV^{u}}{D\lambda}## And this can also be written in terms of the covariant derivative, ##\bigtriangledown_{k}## by ##\frac{DV^{u}}{D\lambda}=\frac{d x^{k}}{d \lambda}...

Do two stars of the same absolute bolometric magnitude have the same absolute visual magnitude? If this is true; does this mean that two stars with the same power output have the same have the same bolometric magnitude and therefore same visual magnitude?

My physics book mentions that a stars luminosity is its total power output at all wavelengths and that absolute magnitude is defined as inherent brightness and NOT luminosity. It then mentions that two stars of the same power output have the same absolute magnitude. Since luminosity is the...

Determine the minimum of $y$ where $y=|x-1|+|2x-1|+|3x-1|+\cdots+|nx-1|$.

Homework Statement Find ## \int_0^{nπ+v} |sinx| dx ## Options are, 2n+ 1+ cosv 2n+1-cosv 2n+1 2n+cosv Homework Equations Integration of sinx is -cosx.The Attempt at a Solution Sin x is + ve from 0 to π, Negative from π to 2π We can make |sinx| as sinx in 0 to π, And - sinx in π to 2π But here...

This is actually a physics problem, but since my question is really about the math involved, I decided to post it in the calculus subforum. I'm supposed to get from the term: $$\lim_{\Delta t → 0} |\vec{v}_r (t + \Delta t)| \frac{\sin \Delta \theta}{\Delta t}$$ To: $$v_r (t) \frac{d\theta}{dt}$$...

So I was helping my sister on homework and there was this problem: 2 abs(2x + 4) +1 > or equal to -3 teacher told her to ignore the -3 and just set it equal to zero. Soo should you? This question got me confused. can't you just go about solving, bringing the 1 to the left and then dividing by 2...

Hello! (Wave) We have to look for numerical methods for the numerical solution of $\left\{\begin{matrix} y'(t)=f(t,y(t)) &, a \leq t \leq b \\ y(a)=y_0 & \end{matrix}\right.$ that have 'great' regions of absolute stability. Methods of which the region of absolute stability contains the whole...

The derivative of ##|f(x)|## with respect to ##x## is ##f'(x)## for ##f(x) > 0## and ##-f'(x)## for ##f(x) < 0##. However, it is undefined wherever the value of the function is zero. I was wondering, though, if the product of this "undefined derivative" and zero is zero.

For the problem of differentiating ##y = x^5(3x-1)^3## using logarithmic differentiation, the solution provides the first step as rewriting the functions as ##\left |y \right | = \left | x \right |^5 \cdot \left | 3x-1 \right |^3##. This confuses me. First, how are we, mathematically, able to...

Show that the equation $|4x-5|-|3x+1|+|5-x|+|1+x|=0.99$ has no solutions.

When solving a separable differential equation, my textbook says this: ln|v-49|=-t/5+C→ |v-49|=e-t/5+C→ v=49+ce-t/5 What happened to the absolute values? I think it has something to do with the exponential always being positive.

-simple procedure designed to absolutely synchronize clocks- Picture the face of a very large clock with a one hand. Let's place a small clock A at the 9 o'clk position of the large clock, and let's place another small clock B at the 3 o'clk position. We use clock A to time the large clock's...

I know this is an elementary question, but it has been some time since I multiplied exponentials, and with imaginary terms combined with absolute values, things get muddled up so easy that I want to clear this up So if I have $$ \Psi (x,t) = c_{1} \psi_{1} e^{- \frac {i E_{1}}{\hbar} t} +...

I just got out of my chemistry lab class at school, and needless to say, I don't think I am going to get a good grade. Basically, I felt like a complete idiot today. My professor was getting frustrated with me because he thinks I wasn't listening to him (even though I was). I never in my life...

what happen to the conductor if it reaches the critical temperature where high conductivity and then back to the original case does it preserve by an amount of high conductivity or high conductivity disappear just a question I'm engineering student electrical power department

Just stumbled across this on my favorite site Dark Roasted Blend: I did not know there was an 'absolute hot'. (it's too large to post here) http://i.imgur.com/iHW7Dwh.png

Homework Statement Make the design of a circuit returning the absolute value of a number of 3 bits . The input and output must be signed , use the complement 2. Show your approach and draw your track using logic gates. I seriously do not understand this at all. What am I supposed to do...

hello sir ...can anyone explain me the value of (U) at infinity with respect to Earth as reference point

is e^{2 \ln{|x|}} = |x^2| or x^2?

i have a simple question, but I'm not sure it can be answered with our knowledge of absolute zero: if an object were to exist at absolute zero, that means it has no energy, correct? if that is true, then if you struck something at absolute zero with another object, would the object with no...

1. (a) What is the distance modulus of the Sun? (b) What is the Sun’s absolute magnitude?2. I found the distance modulous using 5log(4.84E-6/10) to be -31.6. I feel like I need the apparent magnitude to get the absolute, my teacher is very vague about what we are given to use. Is there a way...