Multiple Definition and 1000 Threads

Homework Statement Our prof has told us we can get help from wherever/whoever we want as long as it isn't classmates. This is a take-home test. The relevant question: You have a three-layer dielectric. | Layer 1 | Layer 2 | Layer 3 | Layers 1 and 3 are semi-infinite. Layer 1 is air (εr =...

Hi there. It's not actually a problem, I was just trying to figure it out, so idk if this is the right section for this post, but anyways: I've managed to derive the expression for the Fraunhofer diffraction in a single slit, such that the distance between a minimum and the central point is...

Homework Statement Two +4 mC charges and two -4mC charges are arranged on a circle of diameter "d" as shown in the figure below. The magnitude and direction of the force on the +4mC charge at the top of the circle is: a) 6.39*10^6 N radially inward b) 1.2 * 10^7 N radially inward c) 2.4...

Doing a T-s and P-v diagram from a real power plant Rankine cycle. The cycle, after the condenser, goes through one pump, and then in series: gland steam condenser 4 closed feedwater heaters 1 open feedwater heater another pump 2 closed feedwater heater boiler Temperature and...

Homework Statement Doing a T-s and P-v diagram from a real power plant Rankine cycle. The cycle, after the condenser, goes through one pump, and then in series: gland steam condenser 4 closed feedwater heaters 1 open feedwater heater another pump 2 closed feedwater heater boiler...

Homework Statement Compound A can react to form B and C according to the following A<->2B Kc=1 A<->C Kc=1 If 1 mole of A is solved into 1 litre of water, what will the concentration of A be after equilibrium has been reached?Homework Equations ICE-tables(?) A<->2B+C Kc=([B]^2[C])/[A] The...

Since there was some confusion previously where this post was mistaken for "homework" let me underline now *** THIS IS NOT HOMEWORK *** I've finished university 20 years ago, so this has nothing to do with any schoolwork or anything like that. I'm simply trying to understand some papers I'm...

1) f(x)=\frac { { x }^{ 2 } }{ \sqrt { x+1 } } \\ f'(x)=\frac { 2x\sqrt { x+1 } -\frac { \sqrt { x+1 } }{ 2 } }{ x+1 } \\ f'(x)=\frac { x(3x+4) }{ 2{ (x+1) }^{ \frac { 3 }{ 2 } } } Can somebody show how you can get from the second step to the third step? I tried factoring x+1 from the...

Homework Statement In a photoelectric effect experiment, the frequency of the light is increased while keeping the intensity of the light constant. What effect does this have? A) fewer electrons will be ejected B) more electrons will be ejected C) the same number of electrons will be ejected...

Homework Statement Solve each equation for solutions on the interval 0 ≤ x ≤ 2∏. 2 sin x = √3 The Attempt at a Solution Okay so I was able to solve this one: 2 sin x = √3 sin x = (√3) / 2 So i got x = ∏/3 ; 2∏/3 ; 4∏/3 ; 5∏/3 I substituted the x's into the original...

Homework Statement I have four equations and have four variables. I need to solve for each of the variables. I am having difficulty figuring out how to do this. My equations are here. http://imgur.com/EOA8I Homework Equations \frac{(x-h)^2}{a^2} + \frac{(y-k)^2}{b^2} = 1 The Attempt...

Homework Statement Let D be the triangular region in the xy-plane with the vertices (1, 2), (3, 6), and (7, 4). Consider the transformation T : x = 3u − 2v, y = u + v. (a) Find the vertices of the triangle in the uv-plane whose image under the transformation T is the triangle D. (b)...

Homework Statement If two forces of equal magnitude act on an object that is hinged at a pivot, the force acting farther from the pivot must produce the greater torque about the pivot. a. False b. unable to decide without knowing shape of object c. True Homework Equations T=rxF...

Homework Statement Circuit as shown: (sorry about the amazing paint skills) The pd is being applied from A to B (C is in the centre of the circle) (1) Determine the relations between the current by reversing V and using symmetry or by any other suitable method (2) Calculate the total...

When dealing with n-particle systems that are identical, is the superposition of them just a mathematical construct, or is it similar to how the state of a single particle can be in multiple eigenstates until its measured. For instance, if I have two fermions: \Psi = \Psi_a(x_1)\Psi_b(x_2) -...

Dear all, I hope someone can help me. I have two experimental groups, A (n=5) and B (n=8) containing biological samples. The samples are used to estimate my parameter of interest, θ. I do this with Markov-chain Monte-Carlo, which gives me a posterior distribution of θ for each of my samples...

Need help differentiating multiple quantities Homework Statement f′(x) = (x − 1)(x − 2)^2(x − 3)^3(x − 4)^4(x − 5)^5 I need help in trying to differentiate this equation. I know could use a combination of the chain and product rule to figure it out, but my teacher said that doing so would...

Homework Statement My question is q.3 in the attachment. I don't really understand the scenario of the question. The Attempt at a Solution For (a), if X = 1, will the model become: y = (b_1)(E_1) + epsilon? So (b_i)'s are the slopes of the models? But what is the assumption of the...

Homework Statement Suppose a third slit of the same width were added halfway between the original two slits. (the original two slits were a distance d apart). When there were just 2 slits, the point C was the center (a principal max), point Z was the first maximum after C, point Y was the...

I was taught that a particle is assigned to a unique quantum state. As a specific example, two bound electrons can't have the same quantum numbers in an atom. And likewise one and only bound electron is assigned to one quantum state in an atom. Yet, I am reading several solid state books and...

1. Ok, so the question is.. Find the exact volume of the solid bounded above by the surface z=e^{-x^2-y^2}, below by the xy-plane, and on the side by x^2+y^2=1. 2. Alright. So, I know that I can use a double integral to find the volume, and switching to polar coordinates would be simpler...

Hi, The picture below is part of the notes given to us by our teacher. In case it doesn't work, it's a double loop with a voltage source on the left arm, a resistor (R1) on the middle arm, and two resistors in series (R2 and R3) on the right arm. all the resistors and the voltage source are...

I'm trying to figure out how multiple AC sources which are in phase would be able to be used sequentially to power a load. This all started as I read some literature about solar PV panel systems which had a wiring diagram to tie output from the inverters directly into the electrical panel split...

Homework Statement I have an equation that looks like func=sin(pi*x*n)*sin(pi*y*m) I was wondering if there was any method (possibly involving for loops) where I could get a plottable function along xy for all the different combinations of n and m i.e. m= 1 n =1 so the function would be...

Looks like a good field to avoid in Italy. Especially in areas where mud-brick walls abound. http://www.bbc.co.uk/news/world-europe-20025626...

Homework Statement Homework Equations The Attempt at a Solution I know that since the charge is negative qo*Vperpendicular would be traveling in the oppsite direction. Which by the right hand rule ultimately affects B. So using the formula F=q0V(perpendicular)*B...

Hey everyone, I was doing a problem in my Discrete Mathematics book and it called for finding an infinite number of counterexamples to the statement "7n+2" is a perfect square (which fails for n=3 at least). In my search for such an infinite counterexample, I tried to find A, n=n(k,A)...

Homework Statement Homework Equations The Attempt at a Solution First I originally tried using kichhoff's rules, but didn't get far. What is throwing me off is they are giving me the current of the battery instead of the voltage. Since I know circuits in parallels all have...

I understand that given two functions f:X→Y and g:Y→X, to say that f is the inverse function of g means g o f:X→X is defined by g(f(x))=idx and to say g is the inverse function of f means f o g: Y→Y is defined by f(g(x))=idy I understand how to find inverses of one variable functions and...

Homework Statement I have this assignment on where I have to make up a scenario and solve for the question. The question is that there is a baby that is being thrown out of building into a moving car, (to keep the baby out of harms way). How fast would the car have to traveling to catch...

Multiple Pulleys! Homework Statement A 60 kg mass and a 10 kg mass are attached together by massless inextensible strings which pass over light frictionless pulleys. One pulley is free to move while the other is fixed. a) The system is initially held at rest by means of a force supporting the...

Homework Statement Does anyone know how to do this? Let's say I had the equation: f(t) = |2t, 0≤ t < 2 |(t^2)-3, 2≤t how would you plot this over 0≤ t ≤4 in Matlab? Homework Equations - The Attempt at a Solution I've tried ezplot but i can't manage getting both...

I guess this is a simple question. Say I am tasked with finding the Taylor series for a given function. Well say that the function is analytic and so we know there's a taylor series representation for it. Am I gauranteed that this representation is the only power series representation for it...

I have two inductors and a capacitor in series, in the order of inductor, capacitor, inductor. I'm not sure if the equation L1+L2+k*√(L1*L2) will work in this case or not, given the inductors are separated (or offset) electrically from each other by a capacitor. So I guess my question is, can...

An experiment is performed to determine a physical quantity and 10 trials are made. The absolute uncertainty in the quantity can be given by a. the mean of the data b. the standard error of the data c. None of the above I'm leaning more towards b because absolute uncertainty has to deal with...

Homework Statement The z-component of the spin of an electron is measure and the value h-bar/2 is found. Immediately afterwards, the spin along a direction making an angle θ with the z-axis is measured. What are the possible outcomes of this second measurement and with which probabilities do...

Homework Statement A 7.40 cm diameter coil consists of 15 turns of circular copper wire 2.3 mm in diameter. A uniform magnetic field, perpendicular to the plane of the coil, changes at a rate of 7.29×10^−3 T/s . Determine the current in the loop. Express your answer using two significant...

Hello, I'm using this this calculator to determine a rough sample size for a multiple regression (20 predictors). http://www.stattools.net/SSizmreg_Pgm.php I don't really understand the effect size? Could somebody tell me if you are using multiple regression (with 20 predictors)...

Hi, I realize that this might be kind of a silly question, but I am in a physics class currently and I'm having the hardest time visualizing what exactly is happening when a 'real image' is formed on the same side as the object (as in the case of an object emitting light on the concave side of...

Homework Statement A 4.27-kg object is thrown vertically upward from the surface of Mercury, where the acceleration due to gravity is g1 = 3.70 m/s2. The initial velocity is v1, and the object reaches a maximum height of y1. What is the maximum height, y2, if the object is thrown with a...

If I am stationary and a sound source moves towards me at a constant velocity, I will hear it (the sound) increase in frequency until it is adjacent to me and then as it moves away from me, I will hear a decreasing frequency. Fundamental stuff right? It works with radio waves and light which is...

i have been learnin java for about two weeks. i have gone through simple programin and some other programs includin GUI through swing. till that i was working with single form programs that can be compiled by using "javac" and executed by "java" syntax.now to try better i downloaded a java...

please help by telling me whether my approach to solve the problems are right or wrong. please refer to the ATTACHMENT for the questions and my approaches... your help is highly appreciated!

Hello, I have a question regarding multiple regression. I am reading a paper in which the author performed a multiple regression to predict the energy consumption of an electric car based on a 27 variables measured during journeys, such as speed and acceleration etc. The author...

Hi all, I've been working on a little side project, but I've hit a road block on the maths for this one. Basically if you imagine a sealed pack of 10 cards, there is a 20% chance that the pack contains one foil (more valuable) card. The mass distribution of the foil cards are (heavier and)...

Homework Statement http://apcentral.collegeboard.com/apc/public/repository/ap-physics-course-description.pdf Page 45 Homework Equations sinθ = opp/hyp tanθ = opp/adj cosθ = adj/hyp G ≈ 10 m/{s}^2 The Attempt at a Solution I know that the weight is a force pointing downwards...

Hey, so my situation is a positive displacement pump churning out 30gpm. Theres a bunch of pipe losses that I can deal with, and then a long 1.5" pipe with 8 possible outlets (you can screw on a hose). When one hose is attached the pressure is a we will say P1 (read from a gauge on the 1.5"...

Homework Statement Prove that p^2 is a mutiple of 3 ⇔ p is a multiple of 3. We are told p is an integer. The Attempt at a Solution If p is a multiple of 3 then p=3.a (aEZ) and p^2 = 3.(3.a^2) which is clearly a multiple of 3 Suppose p^2 is a multiple of 3. Then P^2 = 3.a and...

The question is ∫3cos25x dx. I tried to solve it 2 ways and got two different answers. Method A. ∫3cos25x dx =3∫cos25x dx u=5x 3∫cos2u (1/5)du/dx dx The 2 dx cancel out leaving 3∫cos2u (1/5)du= 3/5 ∫cos2u du= 3/5 ∫(1/2 + 1/2 cos 2u) du= 3/5( (1/2x)+∫1/2 cos 2u du)= 3/5( (1/2x)+1/2∫ cos 2u du)=...

Hi guys (and gals) Say, i have a solar panel rated at 100w 12v with the following specs: Short circult current(Isc): 6.01A Open circuit voltage(Voc): 21.5V Optimum operating current: (Imp) 5.52A Optimum operating voltage: (Vmp) 17.78v Maximum power: (Pmax) 100W And I decide to...