MasteringPhysics: Homework 12 - Google Chrome @ https://session.masteringphysics
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MasteringPhysics: Homework 12 - Google Chrome @ https://session.masteringphysics.com/myct/itemView?assignmentProblemID-62040000 General Physics I Signed in as Zachary Byington Help Close Homework 12 Item 1 Resources v 1 of 16 | next Item 1 Submit Hints My Answers Give Up Review Part Learning Goal Correct To understand the conditions necessary for static equilibrium Look around you, and you see a world at rest. The monitor, desk, and chair and the building that contains them-are in a state described as static equilibrium. Indeed, it is the fundamental objective of many branches of engineering to maintain this state in spite of the presence of obvious forces imposed by gravity and static loads or the more unpredictable forces from wind and earthquakes Part B As an example, consider the case of a board of length L and negligible mass. Take the x axis to be the horizontal axis along the board and the y axis to be the vertical axis perpendicular to the board. A mass of weight W is strapped to the board a distance r from the left-hand end. (Figure 1) This is a static equilibrium problem, and a good first step is to write down the equation for the sum of all the forces in the y direction since the only nonzero forces of F-0 that exist are in the y direction The condition of static equilibrium is equivalent to the statement that the bodies involved have neither linear nor angular acceleration. Hence static mechanical equilibrium (as opposed to thermal or electrical equilibrium) requires that the forces acting on a body simultaneously satisfy two conditions What is F Your equation for the net force in the y direction on the board should contain all the forces acting vertically on the board Express your answer in terms of the weight W and the tensions in the two vertical ropes at the left and right ends TL, and TR. Recall that positive forces point upward that is, both external forces and torques sum to zero. You have the freedom to choose any point as the origin about which to take torques Each of these equations is a vector equation, so each represents three independent equations for a total of six. Thus to keep a table static requires not only that it neither slides across the floor nor lifts off from it, but also that it doesn't tilt about either the x or y axis, nor can it rotate about its vertical axis Submit My Answers Give Up Figure 1 of! Part C This question will be shown after you complete previous question (s) Part D This question will be shown after you complete previous question (s) Part E This question will be shown after you complete previous question (s) 3:22 PM 4/12/2016Explanation / Answer
Fy = TL + TR - W = 0