Moments Definition and 598 Threads

Homework Statement Four small spheres, each of which you can regard as a point of mass 0.200 , are arranged in a square 0.400 on a side and connected by light rods. The picture has 4 spheres connected by rods in the shape of a square. Theres a point O in the middle of the square and a...

Homework Statement Hello~ I just had a general question about moments and finding them~ I have no idea how to! In my statics class the professor gave us the Moment about o = r X force, but it gets confusing with more than one vector on more than one plane... and there is also this thing...

Homework Statement http://img510.imageshack.us/img510/7663/26160035im5.jpg Homework Equations principle of moments The Attempt at a Solution I took moments about the base of teh retort stand : (220 X x) = 228 X 9 x = 9.33 which is wrong as the question says show that it is...

Hi guys, I am having difficulty understanding moments and equilibrium. I have attached a diagram of a sample problem. The red Arrows are T1 resolved into X and Y components. Let's say that I want to find the equilibrium equation for the moments about A and B. I realize that forces...

Hi, ii was just wonderin how to work out the force exerted on two separate pillars with a beam of 120kg resting on top of them thanks

1. http://img337.imageshack.us/img337/520/fic06p090bk7.png http://img337.imageshack.us/img337/2763/vqc06p090je0.png [/URL] 2. \sumMaboutapoint \sumFy \sumFx 3. Well firstly i just looked at it as a whole to see if i can figure out any of the reactions at F or B. I am confused...

Hi there, quick conceptual question just to make sure I know what I am doing... I am given two forces, F1 and F2, in vector form with given magnitudes. (I) Find the resultant force about point P (given). (II) I am also asked to find the Moments of the resultant force about point P. (I)...

Hi there, quick conceptual question just to make sure I know what I am doing... I am given two forces, F1 and F2, in vector form with given magnitudes. (I) Find the resultant force about point P (given). (II) I am also asked to find the Moments of the resultant force about point P. (I) I...

Homework Statement (Q) A beam 4m long is supported at the left hand side by a hinge support and on the right by a roller support. It is under a non-uniform load intensity throughout by a load intensity given by: w = 25Cos(pi x/8)kN/m. Write equations for the shear force and the bending...

I need some help with number 4.16? well actually I just can't understand the question.. what I did is calculate all the moments with respect to A.. but I don't know if this has some relevance to the problem.. \sum MA= -2 (18.49) - .8 (4.5) +.8 (5.51) I took the counter clockwise direction as...

Homework Statement http://www.tunerspec.ca/school/question_oct16.jpg Homework Equations M=FD The Attempt at a Solution http://www.tunerspec.ca/school/work_oct16.jpg I'm having trouble solving for B by adding the moments about the point A. I am getting an answer of 4.31kN...

Homework Statement The four masses shown in the figure below are connected by massless, rigid rods. http://i241.photobucket.com/albums/ff4/alg5045/p13-17.gif a.) Find the coordinates of the center of mass if Ma=100g and Mb=Mc=Md=230g. b.) Find the moment of inertia about an axis that...

Homework Statement It's number 4 I'm doing Homework Equations ΣmomentA= 0 ΣFx= 0 ΣFy= 0 The Attempt at a Solution i've got the correct answers i think, but I'm not sure how to draw the shear force and bending moment diagrams because of the moment that's included. i did draw...

[Urgent]Assignment On Couples and moments Homework Statement Two coplanar couples equal and opposite moments balance each other Hint: Case1: lines of action constituting the couple intersect Case2: lines of action constituting the couple do not intersect Above is what the lecturer...

is there a relationship between the two? its been bugging me for a while. can't find the answer.

I think I am getting the wrong answer here, but I don't know why. Would someone please be so kind to go through this basic stuff. Question: The force F exerts a 200 ft-lb counterclockwise moment about A and a 100 ft-lb clockwise moment about B. What are F and theta?Attempt: M_A = 2 F \cos...

Hi, As part of a school project on statistics, I'm trying to calculate some parameters of collected data. I've the marks of 50 randomly sampled students in 6 subjects. I'm trying to calculate their skewness. Since the inbuilt Excel function to calculate skewness uses an estimator I've never...

Moments & couples 2D (for now) (cant move on :( ) Hey guys and girls, I am new to this forum but been looking at it for a while, its a great read and always a challenge here or there, but for now i was hoping to get a little help :) Homework Statement The direction of the two thrust...

Homework Statement Consider a thin rod of length L which is pivoted at one end. A uniform density spherical object (whose mass is m and radius is r = 1/6L) is attached to the free end of the rod. The moment of inertia of the rod about an end if I = 1/3 mL^2. The moment of inertia of the...

Homework Statement Consider 3 objects of equal masses but different shapes: a solid disk (radius R), a thin ring (radius R), and a thin hollow square (side 2R). The ring and the square are hollow and their perimeters carry all the mass, but the disk is solid and has uniform mass density over...

when there is enough block ... here is my problem. a hyperbola having F(-5,0) and D(5,0) and difference of focal radii 6. We can use |PF - PD|= 6 or PF - PF = \pm6. I apply the distance formula ..eleminate radicals and simplify. I get 16X^2 -9y^2=144 Divinding both sides by...

Homework Statement 1.Describe how you would find the centre of gravity of a piece of cardboard of irregular shape. 2.The figure represents a tray held horizontally by a glass of water. The tary has a weight of 6N amd supports a drink of weight 3N.The waiter provides a force at P. The tray...

Homework Statement Hi I have a physics exam tmorrow and I was hoping I could get a little help with the moments problem. I attached the drawing and the question asks: a-1. State the principle of moments b-1.Write down expressions including W, Rc and FA for (i)the total counter clockwise...

A uniform scaffold pole of length 5m has brackets bolted to it as shown in the diagram below. The mass of each bracket is 1kg. http://img502.imageshack.us/my.php?image=mechanicseb9.png The centre of mass is 2.44m from the left hand end. What is the mass of the pole?My attempt: I tried using...

Hi all, just having a little trouble getting my head into the following problem. (See attached picture) The picture shows a robot leg, assuming the rest of the leg joins onto something rigid, I need to calculate the torque the motor is required to have to resist the 333g making it...

Homework Statement A large disk of mass M and radius R is spinning like a CD of merry-go-round - that is, about an axis perpendicular to the plane of the disk. It is rotating at an angular velocity (omega initial). At some instant, a sphere of mass M/4 , which is initially not rotating, is...

So I have a point A on a graph with x and y axes. From the origin, the point is 3r to the right, and 1r up. I'm to find the Moment of Inertia along the x, y, and z axes. I've found the x and y moments, but not the z and I'm not really sure on how. I'm not getting any ideas from the graph...

Homework Statement Two plasterers Bill and Dave of mass 45kg and 65kg respectively stand on a unofrm plan ABCDEF of length 4m and mass 40kg. The plank is supported at C and E where C is 1m from A and E is 1m from F. Plasterer Bill stands at B which is 0.5m from A and plasterer Dave stands at D...

First time posting hi guys and thanks for the help before i even start :) here goes, i am on question 4 and I am not the best with this but to be far i am not 100% sure on the question here goes An aircraft flies throught still air at a velocity of 100ms-1 due East. However due to a wind...

Homework Statement Consider the Hydrogren atom in a magnetic field of 2T. If the atom is in the ground state (orbital angular momentum L=0) a) Write down the magnetic moments of the proton and the spinning electron b) What is the splitting of the energy of the ground state in eV due to the...

Homework Statement See attached file Homework Equations M_A = Fd The Attempt at a Solution I using the above equation..just summing all of the forces and their directions but I keep getting the wrong answer(distances from the moment). I also tried summing all the forces from...

If the sum of all moments about a point A of a body is 0, will it then be 0 anywhere else on the body? (I'm working in 2-D)

1. How can turning moments be applied in everyday life? It may be advantageous to give worked examples in each case. 2. Can I use wheels & wrenches as examples? Can you please give me more examples? 3. I really don't know what examples I could work from the wheels and wrenches.

Personal experience, hearsay, unsupported rumors, famous examples, what are the best examples of "making do" with inferior, or an eclectic and seeming useless selection of parts to successfully solve a real problem? http://en.wikipedia.org/wiki/Rube_Goldberg_machine Probably one of the best...

Moments of Inertia--Big Confusion Hey, 1. Using the conventional method to calculate moments of inertia of rigid objects which says we should divide the object into small pieces each of mass dm and then calculate the integral. is it an exact calculation or an approxximation? so far my...

Can anyone give me ideas/hints on how I should go about this?

The moment of inertia about an axis along the length of a rod is zero, correct?

Hi, I'm in the middle of programming an inertia system and am only really just starting to appreciate what the heck inertia is :) I have been taught inertia, but I haven't actually applied it in a real situation (all my exams and tutorials have resulted in formulae giving answers like...

Please could someone tell me how to work out the attached moments question as I've really no idea how to do this one. I'd be really grateful for any help. Thank you. Cathy

Please find the attachment below. Thanks

Ok I have this question where there is a beam 12m long, there is a pivot 3m along the beam (A) and another 10m along the beam (B). There is an elephant at the left end of the beam that weighs 10,000N and the weight of the beam is 4000N, I need to plot a graph of the distance moved (m) against...

It can be shown that if a hamiltonian is invariant under space inversion and if an eigenstate is non-degenerate, then the state is either even or odd in each position coordinate. So if there is a perturbation given by a uniform electric field, which has: H_1 = - \vec E \cdot \left( \sum_i q_i...

When trying to understand moments...two particular things bother me. First Question First...if the unit for moment is defined as a force x distance, a Newton-Meter perhaps, what the hell does that mean? A Newton is very self explanatory...the amount of force needed to accelerate a...

A roller whose diameter is 1.0m weighs 360N. What horizontal force is necessary to pull the roller over a brick 0.1m high, when the force is applied (a) at the center, (b) at the top of the roller. I need a diagram showing the forces acting at the point of contact between the roller and the...

The books said that total magnetic moment of an electron is spin + orbital magnetic moment. But is the orbital magnetic moment realistic quantum mechanically? I thought electrons dosen't have a trajectory. The Stern Garlach experiment showed that silver atoms only split into two paths after...

How often do you have them? You know those moments when you have been blindly banging your head against that wall when all of a sudden the wall disappears and you have a moment of satisfying clarity. Understanding ( or at least the illusion or temporary understanding ). What was you latest...

Hello, This is probably really simple but i don't know if this is the right way to work out the answer i have attached an image containing the problem. I know how to get F2 : Taking moments about A: F2 Cos 60 = 1500 F2 = 3000N But then it says to find F1 using the principle of...

Hey! My teacher gave me a very challenging problem on QM. I've only had one introductiary course, but he said he wanted me to figure this problem out by using whatever resources, so now I turn to you guys ;-). The problem is the following: London attraction forces can be thought of as...

I'm in an aerodynamics class, and I have this canard configuration I'm trying to figure out for a final exam. I need to find the sum of the moment about the center of gravity. I may cannot be helped without the drawing being posted. So far this is what i have: Mcg = Mac - (lcg + lw)Lw +...

I've attached a screenshot of the question. This is what I've tried so far: I've calculated the initial energy of the system (which is all potential energy): Energy of disc: 0.5*I*w^2 + 0.5 *m*v^2 + m*g*h = 0 + 0 + 0 Energy of arm: 0.5*m*v^2 + m*g*h = 0 + 4*9.81*1.5Cos(45) = 41.62...