Approach Definition and 545 Threads

  1. B

    Optimizing Aircraft Approach Path with Stewart Calculus

    http://www.stewartcalculus.com/data/CALCULUS%206E%20Early%20Transcendentals/upfiles/projects/ess_wp_0205_stu.pdf I'm sure this question has already been asked in some form so if I'm repeating, my apologies. I’m not looking for an answer (not trying to have others do my work for me). However...
  2. Deveno

    Proving Normality in G: An Elegant Approach?

    I was asked recently to prove that if N is normal in G: G solvable iff G/N and N solvable. now, I was able to do so, but I wasn't very happy with my proof. ==> the way I approached this was to form the images of the Gk/G(k+1) under the canonical homomorphism G-->G/N to prove G/N...
  3. Z

    Estimating Car Engine Temp. with Load: A Simplified Approach

    Hello Can someone tell me basic equation of car engine temp. that depends on load. I don't need a precise equation - i need something simplified for simulation.
  4. A

    Distance of closest approach for two protons

    Problem is: given the distance of closest approach in a coulombic fields is: d=\frac{1}{4\pi\epsilon_{o}}\frac{Z_{1}Z_{2}}{mv^{2}} calculate the distance for two protons with velocity v=3X10^5 m/s and mass m=1.7X10^-27 kg Can someone please advise on whether I should plug in the mass...
  5. R

    How to Approach Solving Set Theory Equalities

    Hi, I'm struggling to understand how to approach set theory equality questions for example: True or false? (A n B) is a subset of (A u B) Is quite simple as its obvious the intersection will contain everything that is in the union But what about a more complex question like ...
  6. U

    Optimising closest approach with third order motion

    I have recently stumbled into this problem trying to visualise a certain economic model and I'm finding the solution is just beyond my reach. As far as I can tell there is a simplification of the problem which is easier and would still be good to have answered. There are two moving point...
  7. R

    Best Approach to Quantum Gravity

    Which of the following is the most promising road to quantum gravity? 1. quantising General Relativity 2. quantising a different classical theory, while still having general relativity emerge as a low-energy (large-distance) limit. 3. having general relativity emerge as a...
  8. R

    Solaculture: A novel biological approach for low cost energy?

    This seems to be a very interesting low-tech system to harness solar energy. I would greatly appreciate any input, critical or supportive, from the many knowledgeable posters who frequent this forum. You can click on the link and watch a short video, or just read the description of how it works...
  9. F

    Naming Concentric Circles: What's the Best Approach?

    how do you name a circle? Obviously you could name it by its centre example a circle with centre at O would be called circle O. but what if you have two concentric circles?
  10. L

    Closest approach of line segments

    I have two sets of line segments, A and B. My goal is, for each segment in A, I want to find all segments in B which approach within some threshold distance. Clearly this can be done in O(n^2) easily enough, but I think it's possible to do better. For instance, if I were working with points...
  11. P

    What Happens when 2 Unlike Charges Approach Each Other Closely?

    Hi everyone, I was wondering if 2 unlike charges are placed a certain distance d apart, they will attract and move towards each other and the attractive force is given by Coulomb's kq1q2/r^2. Since r cannot be equals to zero as it would imply that the 2 charges exist as the same point in...
  12. A

    Is this a reasonable approach to calculating pressure difference?

    Homework Statement What is the pressure difference between points A and B (point where glycerol and air heads meet) in the picture, if d1 = 0.50 meters, d2 = 0.25 meters, and d3 = 0.71 meters and d4 = 0.86 meters. (ρH2O= 1.00 x 10^3 kg/m^3, ρgly = 1.25 x 10^3/m^3)...
  13. L

    Length of a curve - A calculus approach

    Now I'm a 16-year old high school student, and as some of you might know, i like math :) I have been studying the integration by riemann sums lately, and i truly love the logical concept. So I decided to create my own formula for calculation of graph curve length (without looking at the present...
  14. R

    New approach to FLT Proof for prime powers of n

    Dear all, here is the new approach how to prove the Fermats Last theorem for the prime powers of n. Thank you all that you have mentioned the Diophantine equations. The proof has still one missing link. It should be proved that l is coprime to (c-b) and the same kind of proof should arise for...
  15. Y

    How Do You Prove Minimum Vertex Degree in Graph Theory?

    I was attempting a simple graph theory question. "Let G=(V,E) be a simple graph with n>=3 vertices and 2n-3 edges. Suppose that every subgraph with m(>=2) vertices has <= 2m-3 edges. Let S be the minimum degree for any vertex in V. Prove that S is either 2 or 3." So I let A be the...
  16. C

    C/C++ How Can I Best Learn C++ Before Starting a Cognitive Neuroscience PhD Program?

    Hello all, I'll hopefully be attending a cognitive neuroscience PhD program next fall and I'd like to learn some programming beforehand (having programming skills helps for lots of neuroimaging labs) Labs I've worked in used UNIX and MATLAB and I'd really like to improve my knowledge before I...
  17. bcrowell

    Mermin's geometrical approach to SR

    N. David Mermin has an interesting geometrical approach to SR that I came across today. He seems to have described it in the following places: 1. Mermin, N. David, "Space-time intervals as light rectangles," Amer. J. Phys. 66 (1998), no. 12, 1077 2. a popular-level book called "It's About Time"...
  18. U

    Solving the 2D Laplace Equationd Approach

    Homework Statement u_{tt}=u_{xx} The Attempt at a Solution Where do I start? I have this wonderful Schaums outline at hand, and by looking at similar (unfortunately unsolved problems) I can guess that the answer will be in the range of: u=F(x+iy)+G(x-iy) I'm saying something in...
  19. T

    Is a problem-based approach beneficial for engineering education?

    "Problem approach" education? Sorry I don't know the exact name for this kind of education in english. One of the Universities I'd like to attend offers a problem based approach for it's electrical engineering degree (I want to become a EE). Basically, you are given a problem every 2 weeks that...
  20. I

    Non-linear dynamics approach to a manifold of a saddle point using power series

    Homework Statement Im taking a dynamics course and I am using The strogatz book Non-linear Dynamics and Chaos I need to solve a problem that is similar to problem 6.1.14 Basically it consist in the following You have a saddle node at (Ts,Zs) which is (1,1). Consider curves passing through...
  21. K

    Projectile angle of approach and height of target?

    Homework Statement For my lab, I need to calculate the height of the ring stands so the projectile can pass through them; as well as the angle the projectile will come at them. I have calculated/measured the following things: Muzzle Velocity: 4.11m/s Vix= 4.02m/s Viy= 0.85m/s Delta Y: 0.87...
  22. M

    Lumped mass approach to wing tip vibration

    Homework Statement Hello, I would just like to make sure I am doing the problem correctly. What I have is a cantilever uniform beam that is fixed at one end and free on the other. Basically, it is a wing and I am using a lumped mass approach to find a graphical representation of the wing's...
  23. S

    Showing Tightness of {fn}: A Measurable Approach

    Homework Statement If for each \epsilon>0 , there is ameasurable subset E1 of E that has finite measure and a \delta>0 such that for each measurable subset A of E and index n if m(A\capE1) < \delta , then \int | fn| <\epsilon ( integration over A) Show that {fn} is tight...
  24. I

    Inelastic collision, two cars approach each other at intersection.

    Two cars approach each other at an intersection. One car has a mass of 928.4 kg and is traveling in the negative y direction with a velocity of 21.4 m/s. The second car has a mass of 951.2 kg and is traveling in the positive x direction with a velocity of 39.5 m/s. If the collision is totally...
  25. A

    Micro and macro internal energy approach

    Why is internal energy not sufficient to compare states? Thank you for your answer.
  26. N

    How Do You Calculate the Closest Point of Approach for Two Moving Objects?

    Homework Statement Two objects 1 and 2 are moving towards each other, 1 along the x-axis and the 2 along the y axis. Initially, object 1 is at (- 28.9,0) (in m) moving at speed v 1 = 13.7 m/s, while 2 is at (0.-36.8) (in m) moving at speed v 2 = 7.5 m/s. How long does it take until the objects...
  27. arivero

    Is there a probabilistic approach to number theory conjectures?

    For instance, let's say that you want to study fermat x^n+y^n=z^n for n=3; do not mind that we already know the answer :-) We could consider the densities of exact cubes, d(n), and then to calculate joint probabilities for d(Z), d(X) and d(Y). The mechanism can be applied, for instance, to...
  28. S

    Elastic pendulum - Lagrangian approach

    Homework Statement A spring of rest length L_0 (no tension) is connected to a support at one end and has a mass M attached at the other. Neglect the mass of the spring, the dimension of the mass M, and assume that the motion is confined to a vertical plane. Also, assume that the spring only...
  29. marcus

    Lecture series on Causal Sets approach to QG

    I heard that Fay Dowker (Imperial College London) is scheduled to give a series of introductory lectures on CS-quantum gravity at Perimeter in October. They've been posting video of talks like this on PIRSA fairly consistently. So I expect Dowker's talks will be online--a short introductory...
  30. N

    A book introducing Quamtum Field Theory from a group theory approach

    I'm looking for a book that describes Quantum Field Theory from a group theory approach for mathematical physicists (with emphasis on the physics part). Ideally I want it to first describe and define groups, representations and irreducible representations. The more rigorous the math, the better...
  31. Mentallic

    Strategies for Solving Integrals with Trigonometric Functions

    Homework Statement \int\sqrt{1+cos^2x}dx The Attempt at a Solution This problem is part of a bigger picture, and I can't seem to figure out how to approach this integral.
  32. B

    Closest Mars Approach to Earth in 5,000 Years: Real or Hoax?

    So I received an email today about how Mars is supposed to be the closest to Earth in like 5000 years and that it should look like a smaller moon directly next to the normal moon. I looked around the internet and some sites say that its a hoax. Does anyone know anything about this at all?
  33. V

    How to Solve Using Undetermined Coefficients: y+3y=-48x^2e^(3x)

    Homework Statement solve using undetermined coeffecients y"+3y=-48x^2e^(3x) Homework Equations x^2e^3x gives a Yp=(Ax^2+Bx+C)e^3x The Attempt at a Solution I can get yc easily which is yc=cos(sqrt(3x))+sin(sqrt(3x)) However, I'm not sure as to how to set it up so that...
  34. L

    What is the Kernel Approach in Non-Parametrised Unbinned Analysis?

    i came across the term kernel approach when reading about a non parametrised unbinned method of analysis. what does this mean? cheers
  35. M

    Electrostatics (Distance of closest approach)

    [b]1. A proton an an alpha-particle are projected with a velocity v=(Ke^2/mL)^0.5 each, when they are far away from each other. If their initial velocity vectors are anti parallel to each other, with a distance "L" between them, find the distance of closest approach.(mass of proton = m, charge...
  36. C

    How do you approach learning a new concept?

    I think I'm more of a visual learner than the average person because I find books never provide enough pictures so I have to come up with my own mental image to represent the majority of the concepts I come across. An example is right now I'm trying to comprehend the concept of a joule second...
  37. N

    Practical approach to building a breeder reactor, help please?

    hi, i am interested in nuclear physics but i don't really want to delve into the complexity of it, so could someone please give me an idea of the practical approach to making a breeder reactor, i do not intend to build one, i just would like to know how i would do it if did want to build one...
  38. M

    Basic limit question (limit of h as h approach 0)

    Hi Why is the lim(h->0) of h = 0? I'm new to this so I'm probably being thrown by the change in variable? Is it because we assume f is a function of h, f(h) = h which we know is continuous from other proofs elsewhere, which gives lim(h->0) f(h) = f(0) lim(h->0) h = 0 thanks
  39. P

    Heuristic approach to the Schwarzschild geometry - Accident of deeper meaning?

    The Schwarzschild solution can be obtained by using Newton for the weak field. However it turns out that this in fact is the exact solution. Is this coincidence or is there more to it? Opinions? http://arxiv.org/pdf/gr-qc/0309072v3
  40. A

    Not really sure how to approach this limit involving integrals

    Homework Statement \lim_{x \to 1} \frac {\int^{x}_{1} \frac{1}{t} dt} {\int^{x}_{1} \frac {1}{(2t+1)}dt} Homework Equations The Attempt at a Solution I am not really sure how I am suppose to approach this problem, I would think that as x approaches 1 the integrals will...
  41. marcus

    Henderson video: spinfoam approach to cosmology

    Henderson gives a good talk. He's been working with Abhay Ashtekar on reformulating loop cosmology as a spinfoam-like path integral---also using GFT (group field theory) where a parameter shows up that may have physical interest (possible connection with the cosmological constant). He got...
  42. S

    Calculating IA, IB, IC: A Parameterization Approach

    I'm studying for a test. The question is: Let A be the straight line segment from -3-4i to 4+3i. Let B be the arc of the circle |z| = 5 going anti-clockwise from -3-4i to 4+3i. Let C be the arc of the circle |z| = 5 going anti-clockwise from -3-i to 4+3i. Define: IA = \int_A 1/z dz IB =...
  43. X

    Lennard-Jones Potential - distance of closest approach

    Here's my solution to the problem of finding the distance of closest approach for two atoms approaching each other in a Lennard-Jones potential, starting with velocities (+/-) v_0: They start with energy T0 = (1/2)m(2v02) which is conserved. Thus, E = T + V = (1/2)m(2v2) + A/r12 - B/r6 = T0...
  44. C

    Need Advice on Unorthodox Approach to Physics Education

    Hi. I recently graduated with a B.A. in Political Science. I've been accepted into a pretty decent law school and could head my life in that very comfortable and secure direction. However I've always had a passion for physics, I spend so much of my free time reading about it, watching online...
  45. I

    Tigh-Binding approach for disordered system

    Hello everyone, I am interested in Tigh-Binding calculation of energy dispersion for non-crystalline material. I am familiar with usual tight-binding approach for periodic structure, but I don’t understand how to use it in case of disordered system, For example cluster (or quantum dot) with...
  46. xortan

    What is the best approach for reducing and returning to analyze a circuit?

    Hello everyone, I am a first year student taking electrical engineering. I have a midterm coming up on Friday on circuit analysis. I get the concept of it but what I am wondering is what is your approach when you have to do reduce and return to analyze a circuit? I am looking for a...
  47. S

    Detecting Melamine Adulteration in Dairy Products: An Updated Approach

    Homework Statement For many years the level or protein in foodstuffs including meat, dairy and cereals has been carried out using the Kjeldahl method. This involves conversion of any nitrogenous compounds to ammonia by boiling the sample of food in concentrated sulfuric acid followed by...
  48. K

    Calculus 3 question- don't even know how to approach this problem

    Find the mass of one turn of wire in the form of a helix with a linear density e^(-z) in lbs/ft. Would I write as <e^(-z)*cost,e^(-z)*sint, t>? Maybe?
  49. M

    My new U substitution approach? is this legal?

    Allow me to explain my new theory, The "Mancini conjecture." Ok...lets say I have an integral like (4-x^2)^(1/2) dx. and letting u = 4-x^2, we get du/dx = -2x, and if I took the second derivative of du/dx...i would get -2 this would be ideal, because I would then have du'' = -2 dx, or -1/2...
  50. BobG

    NASA NASA Scientists Plan to Approach Girl

    NASA Scientists Plan to Approach Girl by 2018. Film at 11 (or right below) http://www.theonion.com/content/video/nasa_scientists_plan_to_approach?utm_source=slate_rss_1 Best of all, her eyes are the color of Magnesium Iron Silicate.
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