- #1

demode

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I was given the problem: "What minimum force is required to drag a carton of books across the floor if the force is applied at an angle of 45 degrees to the horizontal? Take the mass of the carton as 40 kg and the coefficient of friction as 0.60.

http://img327.imageshack.us/img327/4383/untitled1yz4.th.jpg

[tex]F\sin(45) + F_n = mg[/tex]

[tex]\mu_k F_n = F\cos(45)[/tex]

Now for the life of me, I can't seem how to solve for F since the question asks for the minimum force.. Will i just need to solve the system of equations that I have?**EDIT**

After some simple math and slapping myself repeatedly for being so blind, i came up with 207.41 as the force.. Would anyone be willing to confirm that answer with me?

**Free Body Diagram (Given by physics teacher)**http://img327.imageshack.us/img327/4383/untitled1yz4.th.jpg

**Equations**[tex]F\sin(45) + F_n = mg[/tex]

[tex]\mu_k F_n = F\cos(45)[/tex]

Now for the life of me, I can't seem how to solve for F since the question asks for the minimum force.. Will i just need to solve the system of equations that I have?**EDIT**

After some simple math and slapping myself repeatedly for being so blind, i came up with 207.41 as the force.. Would anyone be willing to confirm that answer with me?

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