Couple Definition and 445 Threads

Hello, 1. Could anyone tell me if taking these classes and this many classes is an overload for a Senior Year in Mechanical Engineering? (Fall 2015 Semester) -Fatigue in Mechanical Design - elective - Manufacturing and Design Concentration - med/hard -CAD - elective - Manufacturing and Design...

It is said that matter curves space and space tells how the matter to move. 1. Suppose I am moving in a street and there is lots of matter like houses etc, how that matter is governing me how to move? 2. And why something say a ball falls downhill from a mountain?, ball should stay at that...

Hi everyone. I'm a sophomore now , majoring in astronomy, and will become junior in no more than 1 month. I have a good command of classical electrodynamics and quantum mechanics. However, I'm confronted with some problems. 1. I want to know more about Astronomy. I borrow Very High Energy...

Homework Statement i need to couple a ray (point source 15 deg) into a fiber with a small core diameter, the fiber located 8cm from the source. the focal distance of the lens is 1.5cm i need to choose 2 possible locations Homework EquationsThe Attempt at a Solution first suggestion: i placed...

Hi, I tried rationalizing the first one but I get zero. \[\lim_{x\to 3}\frac{\sqrt{19-x}-4}{\sqrt{28-x}-5}\] \[\lim_{x\to 3}\frac{-x-3}{(\sqrt{28-x}-5)(\sqrt{19-x}+4)}\] Here is my next question. \[\lim_{x\to 0^{-}}\left(\frac{3}{x}-\frac{3}{|x|}\right)\] f(x)=\begin{cases}-x, & x<0...

Homework Statement Usually in any question will the magnitude of the couple(friction) be given or is it possible to find the couple from the co efficient of friction between the rotating object and the axis ? Homework EquationsThe Attempt at a Solution

If a material is doped (introducing positive dopants to the lattice) there will be a build up of negative cahrge around them, screening. I have a couple of questions that seem obvious but I'm still a little unsure: 1) how would more screening effect resistivity? I would assume that a build up...

Hi guys. I'm new here and I want to ask you if anybody of you have some ideas to solve this two problems: 1. Consider single field inflation in slow roll regime, at which the slow roll parameter ǫ decreases in time. Take any inflaton potential consistent with the CMB and galaxy distri- bution...

For the simplest case you have a feedback resistor and an input resistor. The non-inverting input is connected to ground. 1. If the gain is only dependent on the ratio of the resistors, is there some sort of advantage in picking higher valued resistors (in the k range) rather than 10 or 20...

Homework Statement Homework EquationsThe Attempt at a Solution THe answer given is B. I can understand why the resultant force is not zero as the field is not uniform. but for a couple, shouldn't the forces be equal. so how can B be correct? also, at some point, the rod will be horizontal...

Homework Statement http://oi58.tinypic.com/2a5d4w3.jpgHomework Equations [/B] So I can just sum up all the forces then sum the moments?The Attempt at a Solution [/B] FBx = 0 lb FCx = 800 cos30 = 692.82 lb FEx = 0 lb FBy = -2500 lb FCy = 800sin30 = 400 lb FEy = -1200 lb Resultant force: FAx...

Homework Statement These are actually two problems that I'm merging into one because each of them seem to have conflicting solutions, and I want to clear this up. Consider a long cylinder (very long) extending in the z direction with a constant magnetization ##\vec{M}=M\hat{z}##. What are the...

had a good nite under the stars on Friday nite ( 16th Jan) did more comet pictures to stack, also imaged M42, Eta Carina and the Small Magellanic Cloud That last one I haven't worked on yet - will add to this thread when done M42 - The Orion Nebula 15 x 30 sec images stacked, 2500 ISO, f5.6 @...

It pains me to even type these out. I realize how many threads there are with very similar questions and to someone well versed in these topics, these questions probably all seem the same. But after reading what seems like all the questions, I feel I'm still confused. 1) In regards to the light...

A man goes into a bar with his dog. He goes up to the bar and asks for a drink. The bartender says "You can't bring that dog in here!" The guy, without missing a beat, says "This is my seeing-eye dog." "Oh man,” the bartender says, "I'm sorry, here, the first one's on me." The man takes his...

Homework Statement Problem is: Replace the 150-N force with an equivalent force-couple system at A Since it is really hard to describe the scenario in words, attached is a link that shows the diagram of the question...

We read that the a couple is a free vector, i.e it does not depend on the point of application. However, please consider the following example: If you apply two equal magnitude forces anti-parallel to each other, one on each side of the wheel, a couple is formed, and so the wheel will rotate...

Please see the pictures. In lab frame, we have rockets A and B initially at rest and clocks in sync. When clocks reach certain time T, both A and B accelerate at 45 degrees to up-right direction. There are inertial observers X and Y, which match the velocity x- and y-components that the rockets...

Hi. I have a lab that concerns this reaction as follows: S2O8 2- + 2e- = 2SO4 2- Can anyone give me a hint as to why this reaction would NOT (and indeed does not as found in the lab) have a potential of ~ 2V from the H+/H2 reference? What is preventing the reaction from reaching its maximum...

Can a W+ boson couple to a W- boson? Say, if a Higgs decays into a W+ and a W-, what would be the Lagrangian density for this interaction? How would you evaluate such a first order diagram?

After being through with Newton's 3rd law of action reaction pairs, there arise a doubt regarding the categorization of force couple (related to torque) of being or NOT being an example of action reaction pairs.

Homework Statement If P=0, replace the two remaining couples with a single equivalent couple, specifying its magnitude and the direction of its axis. The Attempt at a Solution Position vector of B(rb)=0.3i Similarly, rd=0.16j+0.17k ∠GCF=atan(16/30)=28.07° ∠DEF=atan(DF/FE)=45°...

Homework Statement 2: Some proofs: a) If ##\{ v_1 , v_2...v_n \} ## are linearly independent in a real vector space, so are any subset of them. b) If any subset of vectors ##\{ v_1 , v_2...v_n \} ## in a real vector space are linearly dependent, then the whole set of vectors are linearly...

Determine the resultant R and the point on the y-axis through which the line of action of the resultant of the loading system shown passes I have attached an image of the problem In my attempt to solve the problem I went about the following steps: 1- I chose my axis to be right in the middle...

Which is the difference between a cosmological and a gravitational singularity? Is there any mathematical tool that relates them? Do they REALLY exist or are they of a nature that simply escapes GR? How can the Big Bang and flatness of space coexist? Could the Big Bang be a local event? How does...

Hey guy, I would like to ask a few question about force and free body diagram. First question, I conduct a compressive experiment a few day back, using compression machine to test the strength of different materials e.g., Aluminium, PVC and Ceramic. However there is one thing that I don't...

Question 1: why is the voltage of a capacitor as t goes to infinity equal to the voltage source? This question has been answered. The steady state voltage is not simply equal to the voltage source. Question 2: So that does that mean voltage and current are always 90 degrees out of phase...

Homework Statement The special-purpoise milling cutter is subjected to the force of 1040 N and a couple of 211 N·m as shown. Determine the moment of this system about point O. (Let's laugh at the text's typo)Homework Equations Mo = R x F + (Couple)The Attempt at a Solution I'm having a little...

Homework Statement The Attempt at a Solution I understand 90% of the problem and how to do it, I just can't wrap my head around how they managed to get 0.3sin30 for that one side in the problem.

Couple moment problems -- Calculate the distance? Homework Statement http://imageshack.com/a/img691/1734/804i.jpg Homework Equations M = F x d The Attempt at a Solution M = Fxd 20Nm = 35N*x x = 0.57m cos 30 deg = x/d d = x/cos 30 deg = 0.57m/cos 30 deg = 0.66m...

A couple questions about a "hot room" concept. I had an idea that I may try to implement should I ever get around to building my dream house. I think of it as a "hot room". The idea is that there is a utility room which is positioned to receive most of the wast heat generated by household...

Hey everyone, for anyone who saw my thread in the chemistry section you know I'm changing my view point to that of the "there are no dumb questions", and with that I have a couple of things I've been curious about for a while regarding spacetime. First off, from reading and research I am...

So I've been spinning my wheels (I guess I should say slipping, haha) on this problem we've been having We have a coupling intended to transfer torque: One side of the coupling is a smaller insert that slides inside of a larger nut. The insert has male threads on one side and the nut has...

Hi all, Suppose we go in space where no gravity and friction exists. If there is a bar, in say - horizontal plane and we apply a force at one end of the bar, in this plane and perpendicular to the bar. Will that bar rotate and translate or it will only undergo pure translational motion...

1. For a non-homogeneous, linear, 2nd order DE, using the method of undermined coefficients, what do you use for the particular solution for e^x and cosx or sinx. For example, if it is x^2, you use Ax^2+Bx+C. 2.For y''-2y'+2y=0 i put y(x)=c_1e^{(1+i)x}+c_2e^{(1-i)x} but got it wrong. The right...

Homework Statement I need to find i1+i2 Homework Equations for i1=0.092<-98.86 i2=-4i1-j10/25=-4i1-0.4 i1=0.092<-98.86 x=rcosθ=0.092cos(-98.86)=-0.0142 y=rsinθ=0.092sin(-98.86)=-0.0909 i1=-0.0142-j0.0909 Therefor...

if thermo couple ammeter full scale deflection is 10 Amp, for 1/5 th scale what is the Reading?

Homework Statement Okay first one looks like this: Solve 1 ∫ (x2+x)dx 0 2nd: A bunny set the world record in 1997 at jumping the highest of all the other bunnies. The bunny's jump under the competition looks like: h(x)=4x-4x2. Where "h" is the height in meters and x is the distance from...

Homework Statement http://i1345.photobucket.com/albums/p679/Duk_Bato/Untitled_zps863917c8.png Homework Equations Tan angle = opposite/adjacent Cos angle= adjacent/hypotenuse Sin angle= opposite/hypotenuse M=F*D The Attempt at a Solution 40(2.83 sin45) -30(4.47 cos26.57)...

I've got this problem right now, which asks me to prove that $$Ccos(\omega_{o}t-\phi)=Asin(\omega_{o}t)+Bcos(\omega_{o}t)$$ This proved to be a bit more difficult than I expected, so I looked up a complete list of trig identities. $$cos(a\pm{b})=cos(a)cos(b)\mp{sin(a)sin(b)}$$ seems like the...

Homework Statement At a time 0.22 seconds after it has been hit by a tennis racket, a tennis ball is located at (6, 8, 0)  m, relative to an origin in one corner of a tennis court. At a time 0.26 seconds after being hit, the ball is located at (6.52, 8.16, 5.88)  m. Calculate the following...

Homework Statement I'm having problems with understanding how to use the right hand rule as it applies to forces and determining moments. If I understand correctly, The fingers point in the direction of the force, then curl in the direction of r, but I'm not sure what r would be in this...

I understand the concept used here, but am unsure about how scientists can be so sure of the actual age of our universe. They explain it by saying it's like pressing rewind, based on the speed that galaxies are moving away from our own, but I don't understand how you can press rewind to find...

Homework Statement A Triangle ABC has sides of length a, b and c labelled according to the usual convention. Forces of magnitude ka, kb and kc act along BC, CA and AB respectively, with the direction given by the order of the letters. By considering the vector sum of the forces, or otherwise...

A Couple of Questions About "Salt" OK - I understand that all salts are ionic compounds, but not all ionic compounds are salts. I also understand that salts can be formed by: * the reaction of an acid & base, or * the reaction of an acid and metal, or * the recombination of ions when...

Homework Statement If F_1 = 100N , F_2 = 120N and F_3 = 80N , determine the magnitude and coordinate direction angles of the resultant couple moment. Homework Equations M=Fd M=r x F MR=Ʃ(r x F) The Attempt at a Solution I found the couple moment for each force: M1=F1d=100(0.2) or...

Homework Statement Given the following structure, determine the value of F such that the resultant couple moment on the structure is 200 pound-feet clockwise. I'm not looking for help here per se, just if this is a valid method of solution: Because the moment of a couple is a free vector...

Hi. I'm studying calculus in high school right now, and I became really interested in how calculus could be developed from a mathematically rigorous point of view. One of my instructors suggested I learn some set theory, so for about a week I've been researching stuff on the internet - very...

A couple of simple questions I'm boggled by... Suppose two people, each in his own craft, set apart by significant distance and stationary to each other. Both crafts accelerate to 1/2 light speed from their origins directly towards each other. This results in a relative speed between the two...

I'm a little unsure of my own answers to these questions. Hopefully I'll clear up my misconceptions. 1. If I measure the E-field and B-field at a point in space where there is an EM wave, would I be able to determine the direction it propagates from? My Ans: I don't think so, since when...