Hard Definition and 1000 Threads

Well I am doing my homework and there are a few problems that are so hard that i can't even try to get an answer... Hoping you can give me tips to get started, Here they are: 1) A world-class sprinter accelerates to his maximum speed in 3.9 s. He then maintains this speed for the remainder...

Homework Statement if {An} converges and lim {An}=L L\neq 0 and {Bn} diverges then does {An X Nn} diverge? prove formally Homework Equations The Attempt at a Solution can anyone give me a hint or show a solution?

I am a freshmen who is interested in studying physics, but I did not take the first semester physics with my Calc 1 this semester. My plan is to take Physics 1 next semester and Physics 2 over the summer semester. The summer semester is longer then a normal one because it is about three months...

1. Suppose P([1/n,1/2])<= 1/3 for all n = 1,2,3,... a) Must we have P((0,1/2]) <= 1/3 ? b) Must we have P([0,1/2]) <= 1/3 ? My answer - Please correct me if i am wrong a) P([1/n,1/2])<= 1/3 for all n = 1,2,3,... lim P([0,1/2]) n-> infinity so then P((0,1/2]) is a...

Hello .. I'm currently trying to choose my degree course and I'm having difficulty in knowing what to do. I know this will sound stupid but I'm terrified of taking IT and/or Science in University and failing in it. Technology in particular because Maths is hard to me and many if not all IT...

At my university, it's a junior-level class, and mine is being taught by the physics associate chair. It's very fast-paced, and he told us the first day of class he would give us the hardest homework problems in the book. Well, he does. Aside from this site and finding solutions online to help...

Homework Statement I've been struggling for the past hours and can't find the difference between "linear system of algebric equation " and "homogenus system of equation" ,I have the oral(writting) exam tuesday and I would appreciate a little help since I passed writting exam and only final...

A ball is thrown upward... hard question?? Homework Statement A ball is thrown up from 64 feet above the ground with an initial velocity equal to 128 feet per second. Find when and with what speed the ball hits the ground. The Attempt at a Solution v = 128 anti derivative of velocity...

Hard problem - dividing the subs ! Homework Statement Anupam brought n > 0 subs, one each of length 1; 2; 3;... ; n, to a grading party. The three TAs distributed the subs among themselves such that no sub was broken, and each TA ended up with an equal total length. For what values of n...

The problem is with energy of electromagnetic field -\frac{d}{dt}\int_V\frac{1}{2}(\vec{E}\cdot\hat{\epsilon}\vec{E}+\vec{B}\hat{\mu^{-1}}\vec{B})dV=\oint(\vec{E}\times\vec{H})\cdot d\vec{S}+\int_V\vec{j}\cdot\vec{E}dV I have this relation \hat{\epsilon}, \hat{\mu}^{-1} are symmetric tensors...

... to becoming a professor. I was looking around and saw how difficult many people say it is to become a uni professor so I am going to skip that question "How Hard is it?!?" but let me just make sure if i have this right Undergraduate(Bachelors) Graduate (masters) PhD. Postdoctorate...

Homework Statement To save fuel, some truck drivers try to maintain a constant speed when possible. A truck traveling at 91.0 km/hr approaches a car stopped at the red light. When the truck is 115.7 meters from the car the light turns green and the car immediately begins to accelerate at...

Problem solved :)

Homework Statement Diagram from picture attached R= 200 + 50sin (2pi nt), n=2 R= 200+ 50sin(4pi*t) mm ThetaDot = 120 rev/minute = 12.566 rad/s Gamma(Y) = 30 degrees Calculate acceleration when velocity is max Homework Equations ar= rDotdot - r*(thetaDot)^2 aTheta=...

Homework Statement Factor completely (cis(x) - cis(-x) )/(2i) + (1 - cis^2(-x))/(i + i cis^2(-x) ) Yes I know that it's just simply sin(x) + tan(x) which equals sin(x) ( 1 + sec(x) ) but however if you write it out in it's proper form (cis(x) - cis(-x) )/(2i) + (1 - cis^2(-x))/(i +...

Does anyone know the stances of prominent physicists (Susskind, Hawking, others) on hard determinsm?

Background: BS physics, double minors in chem and math, c/o 2008. Started with chem major, but switched to physics for interest/challange. No absolute career goals, but always considered bigpharma as a good place to go. Considered physics grad school, but never that interested in teaching...

when i started learning in the faculty i thought that if i would solve every housework every class work understanding the laws explained in the lecture. then i would get a high grade. but it was not the case. many times i heard in the end of the course sometimes by the professor himself...

Hey folks, another question. What is the difference between hard and semi-hard scattering events? In terms of energy I found for both s >> t, so where does the difference lie? Thanks, Earth's

AMC Question HARD! While doing the Year Eight AMC (Australian Maths Competition), I came across this diffucult question... (By the way, this isn't homework :P) "I have a list of twelve numbers. The first number is 1 and the last number is 12. Each of the numbers is one more than the average...

Does a hard drive weigh more when data is stored in it?

I've been going at this problem for at least 3 hours :cry: Just need to find the integral for: INTEGRAL(x^3e^x^2) / (x^2 + 1)^2 dxI've tried all kinds of different methods, filling up at 4 pages in my notebook! I think this is the closest I've gotten :confused: First I broke up the numerator...

The theme seems to be that Academia positions are far and few between, so it that the same for National Labs too? Thanks.

I don't want to "pirate" any movies, but would like to rip DVD's that I bought into my computer so I can put them on my iPod. Are there ways to rip copy protected DVD's with many chapters/episodes etc? Which software allows me to do it? Is it legal?

Homework Statement a 1000kg car negotiates a banked friction free track or radius 25m with speed 30m/s to what angle to the horizontal is the road banked? Homework Equations The Attempt at a Solution tried to calculate the normal force of the car, to find the angle between the...

Homework Statement A commuter airplane starts from an airport and takes the route shown in the figure below. The plane first flies to city A located 175 km away in a direction 30.0° north of east. Next, it flies for 150 km 20.0° west of north to city B. Finally, the plane flies 190 km due...

um, I'm having a hard time understanding some terms and equations in semiconductors, particulary 2 equations and 1 term(fermi function,density of state function, and fermi level). My understanding of fermi function is somewhat the probability of an energy state to be occupied by an electron. for...

Hi, I'm just wondering if anyone can help me with this equation: I need to determine the values of A,B and C from the given equation. \frac{A}{(x-1)} + \frac{B}{(x+1)} + \frac{C}{x} = \frac{5x^2+2x+1}{x^3-x} I've tried to simplify it by factorising the denominator on the LHS to x^3 - x...

Homework Statement \mbox {1. If f(x) is a positive and continuous function in [1,\infty)\ and\ \lim_{x\rightarrow \infty} f(x)=0 } \mbox {Prove or contradict:}\\ \mbox { If } \sum_{n=1}^\infty f(n) \ \mbox {is converget then} \ \int_{1}^\infty f(x)dx \ \mbox {is also convergent.} \mbox...

Homework Statement see attachment The Attempt at a Solution for part a): I tried to use the equation N2/N1= I1/I2 I got 12A, instead of the answer (24A) can someone please show me how to do this? I missed class one day, and now I'm lost

Homework Statement Given integers 4, 8, 7, 5. An inversion occurs when one integer is larger than an integer that follows it; thus, in the above arrangement there are two inversions due to 8 and one due to 7 or three inversions in all. There are twenty distinct possible integers arranged in...

Ok so I'm currently doing the calculus and vectors course (we sacrificed integrals to include vectors) And I'm finding that course really difficult. I don't know what it is but man no matter how much time i spend on it (atleast 3 hrs a day) i can't seem to get it. Well that's sort of a lie. I...

I understand the general aspects of how a hard disk drives works. I have gone deeper and have learned about the various types of magnetoresistance, both AMR and GMR. I understand the fundamentals of how these systems work compared to older units. But people keep telling me that the data...

Homework Statement A French and a U.S. submarine are moving directly towards each other during manoeuvres in still water. The French submarine is moving at 50.0 km.hr-1. It sends out a sonar signal at 1100.0 Hz. The frequency detected by the French submarine (reflected back from the U.S...

The girl is going on a bungee jump. She weighs 65 kg. The rope is 11m. In total, she fell 36 m. The first 11 m is free fall, and another 25m is simple harmonic motion. 1) k of rope 2)max spped 3)what point when she has max speed 4)amplitude of rope 5)how long does it take Homework...

Hi! I need to know what's the "hard bremsstrahlung emission". I googled it but it only showed papers (and few because my university don't have access to many) on experiences that at some point mention this effect but don't explain it. I know what's bremsstrahlung emission, just don't know...

hard circuit problem! help please! I need help with question number 4. The problem and relevant equations are attached. I= Current flow in Amperes V= voltage in volts The Attempt at a Solution I found the effective resistane (4.4 ohm) However, I could not find I3 or V5 I thought to...

Goal: You want to train your Senior Manager. He needs skills: x1, x2, x3, x4, x5, x6, x7, x8, x9, x10. You are to choose from the following programs/courses that fulfills all the senior manager's skill needs at the cheapest cost. p1 has x1, x3, x4 at $500 p2 has x3, x5, x9, x10 at $1000...

By what tools can we evaluate limits like this: Lim (sin((n+1)/n^2) + sin((n+2)/n^2) + ... + sin((2n)/n^2)) as n->infinity I've played around with Maclaurin polynomials, squeeze and Stolz–Cesàro theorems...

Homework Statement find the Laurent series for \frac{z+2}{z^{5}-8z^{2}} in 2<|z|<\infty Homework Equations The Attempt at a Solution Well, I factored out z^{5} in the denominator, which left me with a geometric sum (since |z|>2). I've come up with...

I have derived the following equation for the velocity of a collapsing shell of a collapsing star. \frac{dr}{dt}=-[GM(\frac{1}{2}-\frac{1}{R})]1/2 I now need to integrate this to find the free-fall time, and the hint is to manipulate the equation into a form where you can use a standard...

Homework Statement µ Q.4 An incompressible fluid of density ρ flows steadily through a two-dimensional infinite row of fixed vanes, a few of which are shown below. The vane spacing is a. The velocities V1 and V2 and pressures p1 and p2 are all constant along their respective stations, (1) and...

Homework Statement The 3m plank shown in section has a density of 800 kg/m3 and is hinged about a horizontal axis though its upper edge O. Calculate the angle theta assumed by the plank with the horizontal for the level of fresh water shown. Homework Equations Whats wrong with the editor...

2 electrons in box, "hard" walls, total energy E. Say we place 2 electrons inside an empty 1m cubed box with very "hard" walls, the electrons can penetrate only a very small distance into the walls of the box. Let us say that any photons produced by the scattering of the two electrons stay in...

I can't exess files from my specfic login only the public files e.g. files that were on my desktop. Any ideas? Cheers

What are Hard QCD processes ?

nm i got it figured out.

What is sum n=1 to infinity n^2/(n^4+1)

Okay here goes, I've read different things online about charging a capacitor so I just want to clear this up once and for all. When you are charging a capacitor, I always understood it as the electrons shifting from the wire connected to the negative end of the battery onto the plate, and the...

[PLAIN]http://folk.ntnu.no/jonvegar/images/math.gif I really need some help here (no program is allowed :smile:)