Normal Definition and 1000 Threads

Normal Matrices Examples (URGENT) I need to produce 2 x 2 normal matrices A and B such that A + B is not normal. I have proven that AB is normal if AB = BA using the Householder matrix form. But I can't find a form for A + B failing to be normal. A matrix A with entries a, b, c, d is going...

There are two types of zeeman effect, one normal and the other one anormal, but why are they called so? I mean what is so normal about the normal zeeman effect and what is so anormal about the anormal zeeman effect??

http://imgur.com/SnHyP What are the mathematical steps and assumptions to reach the conclusion that length(ab) ≈ dx + ∂u/∂x*dx ? If you consider the the squares of the gradients to be negligible, you still have a square root and multiplication by the constant "2". What other assumptions do...

http://imgur.com/SnHyP What are the mathematical steps and assumptions to reach the conclusion that length(ab) ≈ dx + ∂u/∂x*dx ? If you consider the the squares of the gradients to be negligible, you still have a square root and multiplication by the constant "2". What other assumptions do...

Hi guys. Please look at the uploaded picture. Normal stress is difined as: σ= P/A. And the Maximum normal stress σ = P/ (b*h/cos(θ)) ?? The right answers should be σAB= 97,7 MPa and σBC = -66,5 MPa. But how do I calculate it? What I have tried: Force AB: 40* sin(60deg) = 34,641 kN...

Homework Statement Two horizontal frictionless rails make an angle θ with each other. Each rail has a bead of mass m on it and the beads are connected by a spring with spring constant k and relaxed length=zero.Assume that one of the rails is positioned a tiny distance above the other so that...

Homework Statement Hi everyone! first post here :) Basically, the question is as follows: Consider a hydrogen fluoride molecule (atomic mass of H is 1g/mole and of F is 19 g/mole). 1. Write the energy of the system in terms of the displacements of both atoms. There are other questions...

Homework Statement Two equal masses (m) are constrained to move without friction, one on the positive x-axis and one on the positive y axis. They are attached to two identical springs (force constant k) whose other ends are attached to the origin. In addition, the two masses are connected to...

Homework Statement 1000 independent rolls of a fair die will be made. Compute an approximation to the probability that the number 6 will appear between 150 and 200 times inclusively. If the number 6 appears exactly 200 times, find the probability that the number 5 will appear less than 150...

how can you tell if the frictional force is great enough to keep a car turning a curb in circular motion based on the coefficient of friction and the normal force?

Where does the normal line to the ellipse x2-xy+y2=3 at the point (-1,1) intersect the ellipse a second time?So I took the derivative of the equation to get: y'=(2x-y)/(x-2y) Then I put (-1,1) into the equation, to get a slope of 1. So, for the normal line I got a slope of -1, which has the...

Homework Statement You exert a force of 131 N [30° below horizontal] onto a 12.6 kg lawn mower, What is the force of gravity and normal force on the lawn mower?Homework Equations Fg= m × g FA (y component) = Sin30° × FAThe Attempt at a Solution The force of gravity is equal to the force of...

Lets assume that liquid superconductors exist. Now I place a magnet above a pool of the liquid. Now will the surface of the liquid remain level or will it appear to have dent in it. I am not sure I kind of back and forth in my head.

Homework Statement Generalize: For arbitrary 0 < p < 1, show that the method giving a and b produces the minimum length interval. Hint: It might be helpful to use local extrema for the inverse function of the distribution function. Homework Equations The method is is talking about is...

Homework Statement This is just a more generalized question, and not really about a specific value. The question was regarding torque, and had a man standing on a ladder like so. The only force (exerted by the man on the ladder) that provided torque was indicated to be mg, but I don’t really...

Hello Forum, If a bike is negotiation a curve, the static friction force will supply the centripetal force F_c. If we go too fast and the friction is not enough we skid along the tangent. There are two forces: the weight W=mg pointing down, the normal (contact) force N pointing up and...

Homework Statement Find all points on the surface at which the tangent plane is horizontal z=x3y2 Things I know: Tangent plane is horizontal then therefore the normal must be vertical in order to be perpendicular. Dot product of the tangent plane with normal is = 0 Normal...

Using the standard normal table in your lecture notes, calculate to four decimal places Table file:///Users/manukumarindia/Desktop/Screen%20Shot%202012-10-29%20at%2011.12.15%20AM.png Work done so far. If X ~ N(22,4), z = (x - 22)/sqrt(4) ~ N(0,1) Thus, P(22 <= X <= 25) = P((22-22)/2 <= z...

I have an incline A that is very steep reaching a vertical height of h and another one B which is less steep with the same vertical height. So using the work energy theorem: in A, KE+work done against friction=mgh so the work done against friction and initial KE is equal to the gain in...

Homework Statement Question - On a statistics examination, the mean was 78 and the standard deviation was 10. (assume normal distribution). a) Find the standard scores of two students whose grades were 93 and 62, respectively. b) Determine the grades of two students whose standard...

Alright, I don't have a specific homework problem here, just a general question. I've attached two pages that I will be referencing. Figure 1. Inclined Plane As can be seen here, the FN = mgcos(∅) Figure 2. Banked Curve It seems as if the opposite is true here. FNcos(∅) = mg...

Scope of this thread is to give a complete as possible answer to the question proposed two days ago by the user simon11 on Basic Probability and Statistic forum... Assume two random variables X and Y are not independent, if P(X), P(Y) and P(Y|X) are all normal, then does P(X|Y) also can only be...

Hello, I'm David. I'm a new member here. Could anyone of you help me? Where can i find the formal deduction of Gauss' Normal Distribution Function? I've read a lot of statistics books and never found that. Where that comes from? It's just curiosity, not homework. P.S.: sorry about my...

I have heard 2 informal explanations for the normal force during a situation like a book resting on a table: 1. The springiness of the atomic lattice in the table attempts to restore its original structure, thus pushing the book. 2. Since there are electrons on the outside of both the...

Assume two random variables X and Y are not independent, if P(X), P(Y) and P(Y|X) are all normal, then does P(X|Y) also can only be normal or not necessarily? thanks.

Homework Statement A ladder of length l and mass m leans against the side of a house, making an angle θ with the vertical. Assume that the ladder is free to slide at the point where it touches the side of the house (there is no significant friction). Find an expression for the normal force...

Anyone know answer to below. If two random variables X and Y are both marginally normal, and conditional distribution of Y given any value of X is also normal. Does this automatically mean the conditional distribution of X given any value of Y also has to be normal? or not necessarily.

Homework Statement What is a mechanism that might cause a rubber band or a string to develop tension in response to a force that you apply? What mechanism explains how walls and tables exert normal forces without bending noticeably? Homework Equations None, since this is a...

Homework Statement Let N(x) denote the CDF of the standard normal density. So, it's the integral of the standard normal density from -∞ to x. Is it true that \lim_{b\to 0} N(\frac{a}{b}) = N(\frac{a}{\lim_{b\to 0}b}) = N(+\infty) = 1? 2. The attempt at a solution This is more of a...

Ok forgetting everything about how Earth is not a perfect sphere, the greatest centripetal acceleration is at the equator. So if you say N - Mg = -Mac, N should equal M(g-ac) which gives a weaker force than the gravitational force. If the net force is a force towards the center of earth...

Let's say we have a point-normal representation of a space: n \cdot P_{0}P = 0 where n is a vector <a_{1},a_{2}...a_{n}> and P_{0} is a point through which the space passes and P is the set of all points contained in the space. In ℝ^{2}, the point-normal representation defines a line. In...

Homework Statement The Gravitron single-car roller coaster consists of a single loop-the-loop. The car is initially pushed, giving it just the right mechanical energy so the riders on the coaster will feel "weightless" when they pass through the top of the circular arc. How heavy will they...

Homework Statement Everything needed is written in the question ( Open the attached image ) Nyhow the required is to find the value of P.Homework Equations Shear stress = \frac{ \Delta V }{\Delta A} eq 1 normal stress = \frac{ \Delta N }{\Delta A} eq 2The Attempt at a SolutionFor the...

General Question Here: Let's say you are swinging a ball around on a string. Will there be a normal force?

How do you calculate the Normal vector to an Ellipse. Radius Vector: r=rx*i + ry*j + rz*k Velocity Vector: v=vx*i + vy*j + vz*k at this point I would like to calculate the Normal to the ellipse. That is as far as I been able to calculate. Any help or suggestions are welcome.

Homework Statement find the normal approximation for the binomial probability P(x = 4,5) where n=14 and p = .5. Homework Equations μ = np σ = sqrt(npq) z = (x - μ)/σ The Attempt at a Solution p = .5 q = .5 μ = 14*.5 = 7 σ = sqrt(14 * .5 * .5) = 1.87 z = (4 - 7)/1.87...

This is my first problem set involving work, so I want to make sure I'm doing it right. Thanks for checking. Homework Statement To push a 25.0 kg crate up a frictionless incline, angled at 25.0° to the horizontal, a worker exerts a force of magnitude 209 N parallel to the incline. As the...

I was looking at this example: http://keep2.sjfc.edu/faculty/kgreen/vector/block3/flux/node10.html and was confused between the difference between \hat{}n and \vec{}r Why is the original vector field not given in terms of a unit vector? And what difference does this make? Thanks :)

Hi everyone, Defined the Fermi Normal Coordinates (which can be seen for example http://relativity.livingreviews.org/open?pubNo=lrr-2011-7&amp;page=articlese10.html" ) is there any heuristic argument to explain why the area element is something proportional to the element of solid angle? I...

Ok so I already know how to solve it by looking at an example my teacher did in class... This is what I did... 4. A 2.00 kg block is held in equilibrium on an incline of angle θ = 70° by a horizontal force vector F applied in the direction shown in the figure below. If the coefficient of static...

Graphics3D[Sphere[{0, 0, 0}]] How do I add a tangent plane and normal vector to this plot? I am not opposed to Matlab or Latex either.

You push a 8.00 kg suitcase across a smooth horizontal floor applying a force directed 35.4 degrees below the horizontal. Someone measures the acceleration of the suitcase to be 1.26 m/s2. Assuming g = 10.0 m/s2, what is the normal force the ground exerts on the suitcase? So is normal...

Homework Statement So the question is, given a set of random numbers, find the mean and the value that will be >= 99% of the occurances. So for a set of random numbers between say, 1-100, if the mean is 50, how do I find out what number will be >= 99% of all observations of the time...

Hi, I have a curve defined by following parametric equation \begin{equation} \gamma(\theta) = 1 + 0.5 \times \cos (N \theta) (\cos(\theta),\sin(\theta)), 0 \leq \theta \leq 2 \pi \ \end{equation} where N is an integer. x and y coordinate of any point on the curve are simply...

Homework Statement A 12cm X 12 cm square plate of AISI 1010 steel (E=200 GPa) us subjected to normal tensile forces of 15 kN and 20 kN on the top and right edges as shown in figure P22. The thickness of the plate is 5mm, and the left and bottom edges of the plate are fixed. Find the normal...

OK, this looks like a differential geometry problem, which it is, but at the end of the day I am trying to figure out why the unit normal and unit tangent vectors to a curve aren't orthogonal, so even if you don't know about DG, please respond. Obviously the two choices for E_1 and E_2...

Homework Statement Here is the question with the solution: The Attempt at a Solution I understand the first part where they find the forces by summation of moments. However I don't understand how they got that area. Why would they take the diameter (0.016) and subtract it from the length...

Homework Statement tall strongman of mass m = 93 kg stands upon a scale while at the same time pushing on the ceiling in a small room.If the scale reads 1062 N (about 239 lb), what is the magnitude of the normal force that the ceiling exerts on the strongman? Homework Equations N=m...

Homework Statement The question ask to find E[X]; E[X^2]; Var(X) for the standard normal distribution f(x)=1/\sqrt{2\pi}e^{-x^2/2}Homework Equations I found \begin{align} E[X]&=\int_{-\infty}^\infty \! x*1/\sqrt{2\pi}e^{-x^2/2} \, \mathrm{d} x\\ &=1/\sqrt{2\pi} ( \int_{-\infty}^0 \...

Homework Statement Your friend's car broke down. You push it to a repair shop 2.0 km away. You gently put your car's bumper against the broken car's bumper and accelerate to a speed of 2.5 m/s over the course of 1 min. If the broken car's mass is 1200 kg, what is the normal force between the...