A Mechanics tries to remove an engine from a car by attaching a chain

AI Thread Summary
The discussion centers on a mechanics problem involving the removal of an engine by pulling a chain at a 15-degree angle with the vertical. The engine has a mass of 180 kg, and participants clarify the distinction between tension in the chain and the horizontal force applied. Tension is defined as the force within the chain, which acts in the direction of the chain, while the horizontal force F is applied outward. To solve the problem, a free body diagram (FBD) is recommended to analyze the forces acting on the chain. Understanding these concepts is crucial for accurately calculating the tension and forces involved.
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Homework Statement


A Mechanics tries to remove an engine from a car by attaching a chain to it from a point directly overhead and then pulling sideways with a horizontal force F. If the engine has mass 180kg, what is the tension in the chain when it makes an angle of 15 degrees with vertical? What is Force

Homework Equations



ƩF=0

The Attempt at a Solution


http://i43.tinypic.com/zl2qgh.jpg


The problem I have with the solution is that I thought because the person is pulling on the chain outward the tension would be in the opposite direction meaning toward the engine. They show T as being in the same direction the person is pulling on the chain. I feel like I have misunderstood what tension means and I would like it if someone could help me understand it.
 
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As used in this problem, the word Tension refers to the force in the chain which is everywhere the same. The word Force refers to the lateral force applied to push the chain sideways, the force F.

Draw a FBD of the point where F is applied to the chain (the block shown in the figure) and do force sums horizontally and vertically). This should give you everything that you need.
 
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