homework ii - chapters 3 and 4 - stanford universitybiomechanics.stanford.edu/e14/e14_h02.pdf ·...

Homework II - Chapters 3 and 4due Friday, 04/15/11, 12:50pm, 370-370

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For this homework, you need to be familiar with chapters 3 and 4 of your book!All solutions for problems 1 - 4 must include a free body diagram!

Problem 1

If the mass of cylinder C is 40 kg, determine the mass of cylinder A in order to hold theassembly in the position shown. Don’t forget to draw the free body diagram(s)!

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Problem 2

Determine the tension in cables AB, BC, and CD necessary to support the 10kg and15kg traffic lights at B and C, respectively. Also find the angle θ. Don’t forget to drawthe free body diagram(s)!

Problem 3

3.1 Determine the tension developed in each wire used to support the 50kg chande-lier. Don’t forget to draw the free body diagram(s)!

3.2 If the tension developed in each of the four wires is not allowed to exceed 600 N,determine the maximum mass of the chandelier that can be supported. Don’tforget to draw the free body diagram(s)!

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Problem 4

4.1 Determine the tension in the cables in order to support the 100kg crate in theequilibrium position shown. Don’t forget to draw the free body diagram!

4.2 Determine the maximum mass of the crate so that the tension developed in anycable does not exceed 3 kN. Don’t forget to draw the free body diagram(s)!

Problem 5

Determine the resultant moment MRO produced by the forces about point O.

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Problem 6

6.1 If θ=45◦, determine the moment MRA produced by the 4kN force about point A.

6.2 If the moment MRA produced by the 4kN force about point A is 10kNm, clock-wise, determine the angle θ, where 0◦ ≤ θ ≤ 90◦.

Problem 7

The foot segment is subject to the pull of the two plantarflexor muscles. Determine themoment of each force about the point of contact A on the ground.

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