Statics Definition and 888 Threads

I hate it when that happens, but whenever I make 2 equations and 2 unknowns, setting the sum of all torques at the known force (rather than the support) and do sum of all forces equation (either of x or y) I get complete canceling of terms and 0 = 0. What does it mean...

This is NOT a homework question. Just trying to understand a basic concept about signs convention... [PLAIN]http://img638.imageshack.us/img638/9334/spring62009.jpg Support A and B allow rotation, but nothing else. Now, if I know W = 400 [N] for instance, using sum of all moments on B...

Homework Statement A flexible chain weighing 41.0 N hangs between two hooks located at the same height. At each hook, the tangent to the chain makes an angle θ = 41.5° with the horizontal. (a) Find the magnitude of the force each hook exerts on the chain. (b) Find the tension in the chain at...

The problem is attached. I have to solve for the force in the member BC. The thing I need help with is solving for the two attachments. I already broke it down into the forces and directions, but what do I do with the lower attachment? How do I find the x displacement of point G from E if I'm...

Electro Statics...What am I missing!? Homework Statement A balloon rubbed against denim gains a charge of 8.0microcoulumbs (I can't do the sign O.o). What is the electric force between the denim and balloon when the two are separated by a distance of 5.0 cm? Homework Equations...

So there is a ladder leaning against the wall. its a 2.5 (base), 6 (height), 6.5 (hyp) triangle. the coefficient of static friction is zero at B (corner of 6 & 6.5). we need to determine the smallest value of Ms at A (corner of 2.5 & 6.5) for which equilibrium will be maintained. They do not...

I didn't use the format because my question is more general. I want to be able to understand the logic so I can apply it where appropriate. We're finding forces (and whether they're in tension or compression) using the Method of Joints and Method of Sections. I don't understand why...

Homework Statement Problem Homework EquationsArea of a semi-circle, area of a semi-sector of a circle, centroid of a semi-circle, centroid of a sector, general equation for centroid of a plate: (X-Bar) * \SigmaArea = \Sigma(x-bar * Area) The Attempt at a SolutionAttempt. I tried my...

Homework Statement a horizontal beam has a pin at 0m(point A), a 90N (-90i) force at .2m(point B), a pin at .4m(point C) and a 180N (-127.3i + -127.3j)at (45 degrees) force at .6m(point D). the pin at point A is attached to a vertical wall with rollers, the pin at point C can't move. The beam...

Homework Statement I have attached a copy of the assignment problem. I have been having serious trouble finding the value of the force P. I know the equations to use for part b and c but I need to know the force P to complete the rest of the problem.Homework Equations a) The problem tells me...

Homework Statement [PLAIN]http://img5.imageshack.us/img5/7653/73215327.jpg The answer in the text is sqrt(15)Mg I am not sure how to obtain this from. Please advise.

Homework Statement The question is: A uniform ladder of mass of 50kg is palced with its foot on a horizontal floor and its top against a vertical wall. Determine the minimum value of themass which must be placed against the foot of the ladder to retain it at an angle of 45degrees to the...

Homework Statement See attachment. Edit: Point A is a pinned connection (has a reactionary force in X and Y direction). Point B is a roller connection (only has reactionary force in Y direction) Homework Equations Sum Fx=0 Sum Fy=0 Sum of Moments=0 The Attempt at a Solution...

1. Three guy wires hold a pole BO as shown. The resultant R of the forces due to the three wires has a magnitude of 1000-N and is directed on the pole BO. Force F2 and F3 have a magnitude of 400-N and 500-N, respectively. The distance from point A to point D is 5-m. Find the tension in cable...

Homework Statement I have a force in three dimensions such that: F=600N Alpha(angle with x axis) = 120 Beta(angle with y axis) = 60 Omega(angle with z axis) = 45 I'm to find the projection of F along the y axis. The Attempt at a Solution I found the force vector for this force by...

Statics...is this problem easy or hard? Yes, I know, easy and hard are relative statements, but I mean easy or hard compared to the other stuff I posted here-- if anyone remembers. Homework Statement A uniform beam, AB, whose length is 2 meters and mass is 10 kg is supported in its tip, A, by...

I really appreciate you guys helping me in all those problems - tiny-tim, nvn! I appreciate the fact there's online support to help me get ready as I'm about to go into a study group with other students which I'll probably be the teacher of (they haven't solved most of what I solved partly...

Questions about statics, mechanics, pulleys... 1) Does the radius of a single, fixated frictionless pulley affect the force I have to apply on one side in order to reach equilibrium with a constant load on the other? Or, will I always have to apply the same amount of force on the other side in...

Homework Statement http://www.engr.mun.ca/~neil/1010/prob11/set2.pdf" In the first problem in the link above, why is the weight pointing upwards instead of downwards? I thought there will be a different force prolly called Fae pointing upwards with the weight pointing downwards. Thanks

I'm trying to construct a bending moment diagram for the situation as below: [PLAIN]http://img42.imageshack.us/img42/633/bmdiag.jpg Where Ra and Rb are reaction forces, L1 and L2 are lengths between Ra and N and N and Rb respectively, N is a force acting perpendicular to the beam and P is...

Hi, the problem states; A crane of mass 30,000kg is secured to the end of a steel plate 6 m long. At each end of the plate are a set of wheels. The crane has a jib of length 15m and is required to lift a mass of 25,000kgs from the end of the jib. The jib is positioned over the 6m long steel...

Homework Statement Hello :) I am stuck on this mechanics problem. Any help would be hugely appreciated, because I am just starting with statics. Thank you in advance . A diagram of the problem can be found here :http:////img97.imageshack.us/i/79504950.png A small crane is used in demolition...

Homework Statement http://img11.imageshack.us/f/screenshot20110117at120.png/ The question is 2.3 Homework Equations Law of cosines and law of sines. The Attempt at a Solution I used the law of cosines to find the resultant force. It is 139.1 lb. However, I get 113.1 degree for...

Hi everyone, I was given a statics problem to determine some forces in a truss. The attached image has the specific problem on it. The correct answer was supplied so I know what I should be getting, and I was able to get the correct answer using the method of joints starting from Pulley C...

Homework Statement A thin rod AB of weight W is attached to two blocks A and B that slide freely in the railways represented. The blocks are linked by a string inextensible and without weight passing through a pulley C. Express the tension in the string in function of W and the angle θ that...

I have setup the map of my curriculum until I will be graduating, and due to thermodynamics and dynamics only being taught once a year, if I do not take them this upcoming semester I will be in school an additional year. I am wondering if it is possible to take statics, dynamics, and...

Hello, I am attempting a problem in an older statics textbook an image of which is attached. No matter what I try, I get a solution of between 0.52 and 0.53 metres and was hoping someone could verify if the textbook answer of 0.48m is right or wrong. Thanks Heaps, Scott.

I recently watched Fourth Kind and was left wondering if it's possible to have statics in captured video. From my understanding, static is mostly associated with radio interference when signals interfere with one another on similar frequencies. Since a captured video records visible light (part...

Guys I need some help with a simple statics problem. I have a bar with a length of Z from point A to point B. A torque is input at point c which is located a length of Y from point A. There are two reaction forces: Fb located at Point B and Fa located at point A. no other forces are...

Homework Statement Two pans of a balance are 50cm apart. If the fulcrum is displaced by 1cm what percentage is the true weight marked up? Homework Equations T=rFsinθ F=mg The Attempt at a Solution I solved for torque of the fulcrum in a hypothetical situation where a mass of 1g is...

Homework Statement 2. The attempt at a solution Ok. so I'm a little bit confused as to how to approach this problem. I would know how to do this problem if it was laying right to left, but because it's vertical, that makes it a lot more confusing for me. I know A = (1/4)(pi)(d^2) =...

Homework Statement A car starts from rest and accelerates uniformly at the rate of 1m/second square to reach a maximum speed of 60kmph. It then travels at this speed for some time and finally decelerates at a uniform rate of 0.5 m/second square to come to rest. If the total distance traveled...

Homework Statement Please see attachment. A uniform massive beam attached to a wall at one end and supported by a cable (also attached to wall). On the free end of the beam is a weight. We are supposed to find the tension in the cable. Homework Equations sum of the torques about...

Hi PF members. I'm a first year engineering student, and recently got my midterms back and was highly disappointed with the statics mark, 55% compared to the class average of 23.8/40, SD 9.1. I did a very large amount of practice from Hibbeler's Statics textbook, 12e, but it seemed that the...

I was given a problem based on statics and I was wondering if anyone could help. A window washer attempts to lean a ladder against a frictionless wall. He finds that the ladder slips on the ground when it is placed at an angle of less than 75◦ to the ground but remains in place when the angle...

Design the three cable support system for a radio tower of height 25 m. This includes specifying the radius R of the supports at point B, C, and D (as measured from the base of the tower) and the diameter of the steel cable. Remarks: - All supports will be erected on a horizontal surface...

Statics Equilibrium Problem -- 3 Force body in equilibrium Homework Statement Q: A T-shaped bracket supports a 150-N load as shown. Determine the reactions at A and C when (a) alpha=90o, (b) alpha =45o A: (a)A=150N going down, C=167.7N,63.4degrees (b)A= 194.5N going down; C=253N, 77.9...

Homework Statement Here is a link to the problem that I am having issues with. http://tinypic.com/r/8zfb5h/7 Homework Equations F x perpendicular distance The Attempt at a Solution http://tinypic.com/r/1tamma/7 I have no idea where to go from there, or if I am even...

Hey guys, I'm kind of struggling with a piece of this problem. [PLAIN]http://img97.imageshack.us/img97/6862/372h.png This isn't my problem exactly (different numbers and units) but I am having trouble completing part c. I successfully did parts a and b by putting the two forces down...

Hey guys I'm having trouble with this simple statics problem. http://img443.imageshack.us/img443/7218/37statics.png [PLAIN]http://img841.imageshack.us/img841/6734/372.png My set up. [PLAIN][PLAIN]http://img543.imageshack.us/img543/9349/ya1x.jpg I'm confused on where I'm supposed to take...

Homework Statement You are given three weights and 3 pulleys. Each mass hangs below a single pulley, and the pulleys are all connected by strings. The middle weight is 3 kg, the other two are each 2 kg. There are two unknown angles at the central pulley, with respect to the horizontal such that...

Homework Statement Please refer to the attachment.Homework Equations Sum of x and y forces = zero Sum of moments about any point = zeroThe Attempt at a Solution By looking at the portion of the string under the crate, there are 3 forces acting on it, namely the two tensions at the side and the...

Homework Statement Determine the scalar components Ra and Rb of the force R along the nonrectangular axes a and Also determine the orthogonal projection Pa of R onto axis a. Homework Equations n/a The Attempt at a Solution I tried setup rectangular coordinate but that didn't work...

[PLAIN]http://img38.imageshack.us/img38/6997/forces99.jpg I'm unsure how to go about solving this. There's 4 unknowns. Ax Ay Cx and Cy but isn't there only 2 equations (sum of forces in x and y direction are equal to 0) that can be created in this situation?

Homework Statement A uniform ladder length L stands upon the ground; the coefficient of friction there is μ . It leans safely against a smooth (friction-free) wall with the base of the ladder at an angle ! to the horizontal. Jim is the same weight mg as the ladder, and so is Jim's friend...

Is it possible to do statics using lagrangians? (specifically building up a compound shape like a bridge from constrained point masses). Where could I see an example of this?

Homework Statement Mass hanging from the pulley in 50kg, the mass on the rope is 1kg. Please see attachment for details. The answer will be in terms on L. Homework Equations The sum of the forces in the y-direction and x-direction are equal to 0. The Attempt at a Solution Adding...

Homework Statement A 500-N concrete block is to be lifted by the pair of tongs shown. Determine the smallest allowable value of the coefficient of static friction between the block and the tongs at F and G. See Diagram: [PLAIN]http://img192.imageshack.us/img192/1315/sprob826.jpg...

When solving for reactions in a 2D diagram as seen below, how does each type of joint affect the summation of forces in the x & y components? My problem asks to find the summation of forces in the x & y components, and has a smooth pin connection in the left of the beam and roller on the right...

Homework Statement Three (3) Identical Cylinders each weighing 80.2 were tied together by a wire and was placed on a smooth horizontal surface as shown determine minimum tension acting on the wire. hint: the answer 20 < Tension < 30 Figure below...