Statics Definition and 888 Threads

Okay, so I am trying to understand the method of sections so I can finish my homework. I look at http://en.wikibooks.org/wiki/Statics/Method_of_Sections" and for the life of me, I can't understand why at the bottom of the page it says Fy=0=2T2 - 981 . Where does the factor of 2 come...

Homework Statement The horizontal member ABC of the rig shown below weighs 1000 lbs and is supported by a pin B and cable EADC. Since the cable passes over pulleys at A and D, the tension is the same along the entire length of the cable. If the rig lifts 3000 lbs at a distance 12 feet from...

Hello, I just found out about this site! I was hoping someone may be able to help me solve this problem

Homework Statement This is a part of a larger problem, but I'm unsure of one part. Picture a door with its center of mass in its geometric center. The door is hanging on two hinges, one at the top and one at the bottom. If the pivot point while measuring torques is considered to be the top...

I am studying statics and more precisely multi force members. I understand the process about solving how to find reactions and forces in x and y directions. However, I have a great tendency to confuse it when if comes to figuring out angles to write equilibrium equations. Any help for me to...

Skip to the bottom for the short version... We are learning moments in statics currently, and I have a problem that asks me to resolve the force given into x and y components, then, using "the principle of moments" aka Varignon's Theorem, find the moment with that same force applied at...

Homework Statement http://www.mypicx.com/uploadimg/1510974339_04192010_1.png Homework Equations The Attempt at a Solution i've got everything i just can't understand how you figure whether the 17.0 and 3.5 are negative or positive, can someone tell me how you figure this?

Homework Statement For the machine element shown, locate the x coordinate of the center of gravity. The picture of 2 different problems are attached Homework Equations V = 1/3*a*b*h The Attempt at a Solution I can figure out the coordinates fine for everything except the triangles...

Homework Statement A cylindrical tank of internal diameter 1.5m and length 2.0m is mounted on a trailer. When the tank is filled with water the combined weight is 55 kN. Find the weight of tank plus trailer with the tank full of methyl alcohol (relative density 0.789). Homework Equations...

Homework Statement A man holds a 6-kg uniform plank. Determine forces at A and B. A is at 1 end of the board and B is 0.6 metres further down. total length is 1.4 m Homework Equations w=mg M=fd The Attempt at a Solution there will be a force down at A and up at B. i think A will...

Hey guys I'm needing some help here its to find the center of pressure on a plane vertical. Sorry guys for the way I've set out all of this but its the only way i know how basically I'm just wondering how to calculate the experimental and theoretical center of pressure of this lab I'm...

Homework Statement Replace the force system with a resultant and specify where its line of action intersects AB from point B. so I guess the imagine didn't work... http://yfrog.com/htstaticspicp I realize it is very small I apologize for that, if anything in the picture is unclear please let...

Hey guys... This problem is driving me bonkers. I really am not asking you to calculate anything but I only ask how to figure out how to get r to use τ = r x F . My professor did not even teach us anything about resultants and 3-d moments Homework Statement Homework Equations MO= τ = r...

Hey guys, this is my first time posting and I really need your help. I'm stuck on this question: A light inextensible string of length 40cm has its upper end fixed at a point A, and carries a mass of 2kg at its lower end. A horizontal force applied to the mass keeps it in equilibrium, 20cm...

Homework Statement A block of wood with a specific gravity of .6 with a volume of 100 cm^3 is made to just float in H2O by hollowing out some of the wood and replacing it with a substance of specific gravity of 6.5. How many grams of wood were replaced. Homework Equations Not totally...

Homework Statement Homework Equations M = r x F, where r is "a vector directed from the line of action of one of the forces to the line of action of any other force" The Attempt at a Solution Well, for the 250 lb couple the r = {3i - 4j - 2k{, F = 250 {3/5i - 4/5j} M = {-400i - 300j} (I...

A rod weighs 180 lb and has a 400 lb load located at point A is suspended in the air by two lines runningfrom point A to points C and D and a ball and socket joint at E. Find the forces for the tension in eachline (rope?, cable?) (A to C and A to D) and the forces at the ball and socket joint...

I have having trouble solving this statics problem, I sum up the forces and have C*cos(30) - B*cos(phi) = 0 in the positive x direction and C*sin(30) + B*sin(phi) - D =0 in the positive y direction B = 275 lbs and D = 300lbs I need to solve for C and phi, I have tried substitution...

This Is really simple I just can't remember what way Sin and Cosine go Homework Statement Here is the problem: 7 (b) A uniform ladder rests on rough horizontal ground and leans against a smooth vertical wall. The length of the ladder is 5 m and its weight is 80 N. The angle between...

Homework Statement See figure. Homework Equations \sum F_{x} = 0 \sum F_{y} = 0 \sum M = 0 The Attempt at a Solution See figure (written in my writing). Are the tensions A and B suppose to be the same? I imagine not because they are at different angles so they have...

Homework Statement Three identical spheres of radius r are at rest at the bottom of a spherical bowl of radius R. If a fourth sphere is placed on top, what is the largest ratio R/r for equilibrium if there is no friction? Homework Equations Obviously F_net=0 since the sphere are in...

Homework Statement Find the tension of the rope. Theta is 45 degrees and A cannot support any moments. Homework Equations Drag=0.5*Cd*(U^2)*A*rho The Attempt at a Solution While everything is known, I am unsure of the setup. I initially thought: T*(cos(45deg))=Drag But it doesn't work if...

Homework Statement See figure Homework Equations \sum F_{x} = 0 \sum F_{y} = 0 The Attempt at a Solution I'm confused as to how to check which systems are equivalent. Do I just have to simply reduce all the systems to one force? I tried comparing systems (a) and (b)...

This is not a homework assignment but a general question about something I found in my textbook. It pertains to fluid statics and dynamics and it says that: We can make the flow of a fluid visible by adding a tracer. This might be a dye injected into many points across a liquid stream or...

Homework Statement http://online.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?courses/phys211/oldexams/exam3/sp08/fig15.gif The force exerted on the plank by the wall is upwards. (True/False) Homework Equations The Attempt at a Solution In statics, when using \sumFy =...

Homework Statement https://online-s.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?courses/phys211/spring09/homework/11/two-beams/fig3a.gif Two identical uniform beams, each of mass "M" and length "L", are symmetrically set up against each other on a floor with which they have a...

I'm considering this for summer at my local university (it doesn't have summer I or summer II options). Is it possible to do dynamics and statics all at once? Thanks!

Mechanics statics problem-- help http://img686.imageshack.us/img686/8831/45170185.jpg I've tried to solve for the maximum weight using moment equation about point A, and it gives way too large value of W as compared to the answer 836lb, so I assume the slipping rather than tipping would...

Statics assignment a bit urgent So here is my assignment. i wish that someone could help me. now i know that this system is statically determinate and that i can compute the forces. my problem is that i cannot figure out how i can compute the moment. the Aim of the assignment is to find all...

Homework Statement Ok so basiclly I know how to do the problems, but I'm confused when to make the force negative and when to ignore the negative. forexample: http://yfrog.com/jastaticsprobp solving part a: Moment at A = -24*39 -(-14*39) = 2028 notice how i had to do -(-14*39) to...

Hello, so I have a statics question which I am having trouble with. The question is : A boom is supported by a ball and socket joint at A and a guy wire at B.If the loads in the cables are each 8kN and they lie in a plane which is parallel to the x-z plane, what is the magnitude of the reaction...

I'm so stuck on this problem. I got it completely wrong on my test because I don't even know where to start. All i recall is that we mus use the vector approach? The problem states: For the figure shown, calculate the reactions at point O due to the tensions in the two cables BA and BC...

Hi, I just have a question about the situation present below: http://img25.imageshack.us/img25/1409/staticstransrot.jpg So basically the goal is to find the deflections of points A, B, and C but I'm having trouble with analyzing this. At point A, there is a roller so the force will...

Homework Statement Using the diagram shown below for a simple reciprocating engine, determine (a) the piston velocity (velocity at point D) and (b) the piston acceleration (acceleration at point D) as functions of the crankshaft angle, θ. The dimensions are as follows: LAB=1.875”, LBD=6.0”...

Homework Statement In the attachment Homework Equations Sum of the forces in the X, Y, and Z Sum of the Moments in the X, Y, and Z. The Attempt at a Solution I don't believe I need help solving the problem, I just need help setting it up. I can find the vector of CD, which...

Hi, can anyone show the correct method of how to solve a problem like this. Got the answers from my book but have no idea how they get them? Thanks James

Homework Statement Two small spheres of 15 g each are suspended from a common point by threads of length 35 cm. Each thread makes an angle with the vertical of 20 degrees. Each sphere carries the same charge. Find the magnitude of this charge. Homework Equations F=(kq1q2)/r^2The Attempt at a...

Homework Statement How come all thetas are equivalent? Please take a look at this drawing http://tinypic.com/view.php?pic=2aahe3d&s=4 The Attempt at a Solution By similar triangles?

Homework Statement The attached solution was given as an answer to a simple truss problem in my sophomore level Statics class. We were to solve for the forces in each member of the truss, using the method of sections for FE and BC, and by joints for the rest. The Hibbeler 12th edition we...

Homework Statement A weight of 10 N is hanging from the top of a three-legged support. The legs are attached to the horizontal floor and form equal angles with each other. Find the forces in the legs, if they form an angle of 30 degrees with the rope. Homework Equations \sumFx=0...

Homework Statement a block of mass m resting on a 20° slope. The block has coefficients of friction µs = 0.80 and µk = 0.49 with the surface. It is connected via a massless string over a massless, frictionless pulley to a hanging block of mass m2 = 2.0 kg. What is the minimum mass m that...

ok, i don't know why, but this question has been baffling me since morning we have two supports both with reactions in x- and y-directions (in 2D), and one external load. now i have tried this with two sets of variables, but the problem i am facing is that in both cases i am getting different...

Homework Statement Homework Equations I think that I need to find the moment of the force F about the line BC first. Then, using that moment, find the "projection" of M_{BC} onto the X axis to find the answer. M_{BC}\sin \left(45^{o}\right) However, I am not getting anything...

Homework Statement The cup shown in the picture is filled with 6 oz of coffee. The center of gravity is located at G. If a vertical force is applied to the rim of the cup a shown in the picture, determine its magnitude so that the cup is on the verge of tipping. Homework Equations sum...

Homework Statement The pipe assembly shown in the picture supports the vertical loads shown. Determine the reactions at the ball and socket joint (point A) and the tension in the two cords BC and BD. Homework Equations Sum of Forces = 0 Sum of Moments = 0The Attempt at a Solution I first...

Homework Statement A 0.5 x 0.8m gate AB is located at the bottomof a ank filled with water. The gate is hinged along its top edge A and rests on a frictionless stop at B. Determine the reactions at A and B when cable BCD is slack. Homework Equations Fx=0 Fy=0 The Attempt at a...

Statics Homework help -- find tension [b]1. In Figure P4.111 determine the tensions in cables BC and BE. Neglect the weights of all members and assume that the support at A is a ball-and-socket joint. The 5200-N force has no x component. (picture is attached below)[b]2. \Sigma Fx = 0 \Sigma Fy...

Homework Statement This is for Statics and mechanics of materials 1... In this project, we were tasked with the re-design of a cheap thermal switch that is to be a component of a low cost product. The switch consists of three metal strips that are bounded on the top and bottom by a rigid...

1. Homework Statement : If the resultant force acting on the bracket is required to be a minimum, determine the magnitude of F1. I understand how to solve problems like this, I just don't understand what it means when it says that the force is required to be a minimum. Any help would be...

Homework Statement A rectangular plate is acted upon by the force and couple shown. This system is to be replaced with a single equivalent force. a) for a(alpha)=40 degrees, specify the magnitude and the line of action of the equivalent force. b)Specify the value of a(alpha) if the line of...