Urgent Definition and 393 Threads

I'm editing a school textbook and have suddenly discovered at the 11th hour that there is a difference between the U.S. cup (236ml), the Canadian cup (227ml) and the British cup (284ml) as well as conflicting results (such as Wiki) that define them differently again - U.S.=250ml, Canadian=240ml...

hi I know about harmonic oscilation, but I'm having trouble understanding how we derived formulas for gravity pendulum. Please read on. If a ball on a string ( string is attached to the ceiling ) is displaced from its equilibrium position by angle A1, then forces on this ball are...

Hi I need help with this problem I have some trouble with partitions: Homework Statement The context is Discrete math /relation Which of these collections of subsets are partitions of the set of integers? 1- The set of even integer and the set of odd integers. 2- the set of...

Homework Statement Hi I have been working on understanding concept fra Measure Theory known as support or supp I know that according to the definition if (\mathcal{X},\mathcal{T}) is a topological space and (\mathcal{X},\mathcal{T}, \mu) such that the sigma Algebra A contain all...

Hi How do I solve the equation x^7 \equiv 21 modulo 66 66 = 2.3.11 so try solving it mod 3 and mod 11 (mod 2 doesn't gives any new information). This tells us x is divisible mod 3, and x^7 = -1 mod 11. One solution to this is x = -1 mod 7. The smallest solution of these two congruences...

Urgent Help Needed! (gases) I need some urgent help with figuring out how to find the distance which 2 gases will meet in this question.. Given: Samples of HBr gas and NH_3 gas are placed at opposite ends of a 1.80 m tube. Question: If the two gases are allowed to diffuse through the tube...

The lead female character in the movie Diamonds Are Forever (lol so random) is standing at the edge of an offshore oil rig. As she fires a gun, she is driven back over the edge and into the sea. Suppose the mass of a bullet is 0.010 kg and its velocity is +720 m/s. Her mass (including the gun)...

(a) show that the vector (2,7,6) be we written as a linear combination of the vectors (1,3,2) and (0,1,2) (b) show that the vector (-1,0,4) can be written as a linear combination of the vectors (1,3,2) and (0,1,2) (c) show that Span((1,3,2),(0,1,2)) = Span( (2,7,6), (-1,0,4))...

Greating my friends, I have just returned home today from heart surgery. I still feeling the effects of the operation, because I'm affried the hospital send me home a bit to early. But I have to have these questions finished before tomorrow. So therefore I would very much appreciate...

I NEED A DATASHEET OR LIST OF ABOUT 50 EACH OF RESISTANCES, DIODES, CAPACITORS, ZENER DIODES AND ICs WITH SPECIFICATIONS LIKE VOLTAGE, CURRENT AND POWER RATING, COMMONLY USED IN ELECTRONICS LABORATORY OF COLLEGE LEVEL I NEED IT URGENTLY WITHIN 12 HOURS

Hey Folks, Can someone please draw me this circuit to a scheme for drawing it on a pcb maker ? I need it urgently, so please help Regards & Respect

hi, i have a qns as follows, any help will be great apperciated. A helium nucleus of velocity " v" enters a magnetic field and moves in a circular path of radius R. A proton having the same initial velocity that enters this magnetic field will then move in a circular path of : a. R/4 b...

A man of mass "m" on an initially stationary boat gets off the boat by jumping to the left in an exactly horizontal direction. Immediately after he leaps, the boat of mass "M", is observed to be moving to the right at speed v. how much work did the man do during the leap ( both to his own body...

Consider the volume V bounded below by the x-y plane and above by the upper half-sphere x^2 + y^2 + z^2 = 4 and inside the cylinder x^2 + y^2 = 1 Given vector field: A = xi + yj + zk Use the divergence theorem to calculate the flux of A out of V through the spherical cap on the cylinder...

A car of mass 1500kg arrives at the foot of a straight hill traveling at 30m/s. it reaches the top of the hill 40 seconds later traveling at 10m/s. The length of the hill is 1km and the gain in height is 120metres. The average resistance to the motion is 500N. Find The average power developed...

A thin film of oil (n = 1.10) is located on a smooth, wet pavement. When viewed perpendicular to the pavement, the film appears to be predominantly red (640 nm) and has no component of wavelength 569 nm. How thick is the oil film? I have tried using 2nt=(m+1/2)wavelength but am having...

Hello. I've got a QFT final tomorrow, and one question is still bothering me. Consider two lagrangians. The first one is L = \frac{1}{2} D_{\mu} \vec{\phi}.D^{\mu} \vec{\phi} + \frac{m^{2}}{2} \vec{\phi}.\vec{\phi} - \frac{\lambda}{4} \left(\vec{\phi}.\vec{\phi}\right)^{2} The second...

this is due on wednesday i would really liketo hand it in on time couple of my questions are in these threads which have not gotten any answers... https://www.physicsforums.com/showthread.php?t=106913 https://www.physicsforums.com/showthread.php?t=106930 For a particle of mass m moving in...

Hey I need help from this as soon as possible. My teacher has given me 2 equations and I need to use them to estimate the time of death of a discovered corpse. 1. \frac {\Delta T_{1}}{\Delta t} = -k_{1}(T_{1} - T_{2}) 2. \frac {\Delta T_{2}}{\Delta t} = -k_{2}(T_{2} - T_{1}) I think...

Hi, I don't know if this is the right place but i am facing a strange problem with my T290i. It is just kept and it just reboots by itself. I do nothing. Once this happened I switched it on it said Charging error stop charging. It was not connected to the charger. All this happened by itself...

Hey, Just need to evaluate this limit, I know that the answer is 0, but I can't figure out how to prove it. Any help is greatly appreciated. lim(x-0) of (sin(cosx-1))/x Thanks.

Hi guys! well I am stuck at the following problem and don't know how to proceed. Plz help me here is the problem \int\sqrt{\tan{\theta}}d\theta here is what I am doing let u=\tan{\theta} du=(\sec^2{\theta}) d\theta 1+u^2=(\sec^2{\theta}) therefore du=...

Ok, If my angular velocity is negative, does that mean I've stopped and now changing directions in terms of my movement? Thanks.

How many elements of unsaturation are implied by the molecular formula C8H10ClNO? Draw Three structure, one containing ether and amine group, one containing amide group, one containing amine and ketone group. I have no clue where to begin and read the chapter. as long as it is...

Hi guys - this is going to seem pretty demanding for a first post but I am desperate. I have a series of 11 questions here spanning Energy/Work and Power, Elasticity and Coplanar Forces that I need masses of help with. I'm finding them to be the most difficult questions of any subject I've...

Hi everyone! Im new here and i urgently need help from anyone whos done an OCR Physics sensor coursework. I am not the brightests bulb in the box in physics and i need to essemble a sensor (potentiometer, thermocouple, resistance bridge or a strain gauge) i was told by the teacher if i wasnt...

I need help in the following question: "The rate of increase of the rate of Inflation is decreasing" Write this sentence in terms of derivatives of average prices. My answer: Let p=price t= time therefore, Rate of change of price = dp/dt = Inflation = I therefore...

Here's the problem: " A particle is in its first excited state with energy E[SIZE=1]a, [SIZE=2]before it decays to its ground state with energy E[SIZE=1]g [SIZE=2]by emitting a photon with an energy hbar*omega (omega = 2Pi*frequency) Why will the photon energy be smaller than DE= Ea -...

I have a PDE problem set due on monday and as I look at the teacher's method for solving this problem it doesn't make any sense to me. I'll show what I have so far. Find the solution of U^2U_x + U_y = 0 that satisfies u(x,0)=x So I started out with the characteristic equations...

What is the efficiency of a 265W motor that draws 4.30A from 120V line? How much energy in Joules does this motor use in 1.50 hour? thanks in advance..

hey everyone. I have a question that I cannot seem to work the answer for. the question is. between 1983-1991 X ~ N (20744,8 xxx xxx) Cant exactly remember the numbers, but how do I get the probability that in 1992 the mean will be at least 21000? I have calculated the Z value which...

I got an assignment in physics that is really hard for me, and I am having a lot of trouble even getting an idea. I am supposed to build a car that starts under its own power. I am allowed to have some sort of trigger device. If anyone has done this in the past or they know of links that could...

hi, i posted this question in the probability forum here but no one is even browsing that one. my brother needs to know this but I'm in exam block right now and can only think of the physics I am studying this term. i can't remember how to figure this out anymore i just know i'll probably...

Ok, i missed the class on finding the inverse of a matrix, and i only have a little bit of an idea on exactly what row operations i can do, when i try to make the matrix = its identity. Another question I am stuck on. Q. I have 2 , 3 X 3 matrixs B and C respectivly. The question is find...

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Hi I have this here matrix A = \left[ \begin{array}{ccc} 2 & 1 & 0 \\ 0 & 1 & 0 \\ 3 & 3 & 0 \end{array} \right] I calculate the eigenvalues and get (2,1,-1) Next I calculate the eigenvectors and get (1,0,1) and (-1,1,0) and (0,0,0) My professor says my third eigenvector is...

Hi every one. Just came acroos a nasty piece and was wondering if you could help me with it. I wasn't sure if it belong to math section or here but science it is for my homework I placed it here. Here is the question. Find the integral of \frac{x}{(x+1)(x-2)^2} I have gotten to some...

Maths urgent help If there is a cubic log with a mass "M" and edges which have a length "2a" and is kept on top of a table,and there is a hole dug inside it right in between two parraral faces of this cube. This hole starts from the middle of one top edge(A) and leads on to the bottom of the...

Hi, as part of my third year degree in Maths I have to give a 10 minute oral presentation of the atom bomb :eek: . I'll start off by quickly giving a historical overview of the experiments that led up to the discovery of radioactivity and the model of the atom etc and then intend to focus on...

I am revising for a test which is next week. I came across this question and I keep getting the wrong answer. Someone please help! A particle has mass 2kg. It is attached at B to the end of two light inextensible strings AB and BC. When the particle is in equilibirum, AB makes an angle of 30...

Have a read and post what you think, Question - Determine the concentration of a saturated aqueous solution of chlorine by back titration. 1. Using measuring cylinders, measure out 25cm3 (enough for reliable results but not wasteful) of chlorine and 40cm3 (excess amount) of reducing agent...

Consider a model in which we let a body fall (radially) into a star, being the simplest example of the schwarzschild solution, in which the angular parts of the solution may be ignored, so that we consider: ds^2 = -(1- GM/r) dt^2 + (1- GM/r)^{-1}dr^2. I have been told that this may be...

I got these two questions i have no idea how to do (i have answers, but no soln's) 1. Given that the affinity constatn Keq for rxn A+B=AB is 5x10^6 and the concentration of free molecules at equillibrium are Afree = 1x10^-4 and B = 1x10^-8, what is the ration of AB to A at equillibrium ans...

The question is: Between two long parallel cylinders of radius "a" and "b" (non-coaxial) and an axal separation of "c", a steady current of "I" flows. (See attachment below) Show that the inner cylinder (radius "a") has a constant magnetic field. Use Ampere's Law. [Hint: 0 = 1 + (-1)]...

Hi I've been working on my assignment for ages and am down to the last two questions (finally) which I've been working on for ages and can't work out. 1. For g(t) = 2sint+cos2t over 0 <(equal to or greater than) x < (equal to or greater than) 4pi show that -3 < g(t) < 3/2 (< greater than...

I have to make this launching device that shoots a projectile (anything I want) in a basketball hoop. I got everything figured out but just need someone to look over my work. The device will consist of a spring inside a pipe. At the top of the spring (where the projectile will be) there will...

Plea for help with kinetics lab -- Urgent I am trying to find a value for the activation energy of the reaction involving potassium permanganate and oxalic acid. I have scoured every free chemistry database on the internet and come up with nothing. Does anyone know how I can calculate this...

Chemistry Speech - Urgent Help! I've got a speech next week upon this topic "outline examples of the selection of metals for different purposes based on their reactivity, with a particular emphasis on current developements in the use of metals". If any-one can help in any matter, little or...

A sample of C10H7OH was found to be contaminated with a small amount of LiBr. The combustion analysis of the sample gave the following results: 77.48% C and 5.20% H. Assume that the only species present are C10H7OH and LiBr, calculate the percentage purity by mass of the sample. First of all...

Our teacher has asked us to verifiy a theory given in our textbook using observations taken by perorming actual experiments using stuff at home or by using ur schools physics or chem lab... the topics we have are kinematics, work and energy, rotational mechanics, gravitation, solid and fluid...