Will the Farmer Move the Stubborn Mule?

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The farmer attempts to move a stubborn 120 kg mule by pulling with a force of 800 N. The static friction force, calculated using the coefficient of static friction (0.8), is 940.8 N, which exceeds the farmer's pulling force. Therefore, the farmer cannot move the mule. The problem is confirmed to be sourced from Knight's physics textbook, which is used in introductory physics courses. The discussion highlights the importance of understanding friction in physics problems.
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Homework Statement



A stubborn 120 kg mule sits down and refuses to move. To drag the mule to the barn, the exasperated farmer ties a rope around the mule and pulls with his maximum force of 800 N. The coefficients of friction between the mule and the ground are mu,s = 0.8 and mu,k = 0.5. Is the farmer able to move the mule?

The attempt at a solution

friction=μs(normal force)
friction=0.8(120kg)
friction=120(9.8)(.8)
frictionS=940.8
940.8N>800N

The farmer will not be able to get the mule to move.


Does this look correct?
 
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Looks good to me. By the way, is this problem from Knight's book? I know I remember it from somewhere...
 
Haha, quite the memory. Yep, taken right from the book.
 
ideefixem said:
Haha, quite the memory. Yep, taken right from the book.

I tutor intro physics and they use that book at my university, so I must have done it recently at a tutoring session. So, my memory isn't that great.:rolleyes:
 

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