Find the Tension in the rope ( really simple )

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AI Thread Summary
The discussion centers on calculating the tension in a rope for a block moving at constant speed on a horizontal plane. The block weighs 25.0 N and has a coefficient of kinetic friction of 0.35. The initial attempt at solving the problem resulted in an incorrect tension of 85.84 N, while the correct answer is 8.75 N. The error was attributed to a misunderstanding of how to incorporate gravitational force into the calculations. The importance of checking units and avoiding calculation errors is emphasized, as these are common pitfalls in physics problems.
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Find the Tension in the rope ...( really simple :D)

Homework Statement


A block pulled by a string is moving on a horizontal plane with a constant speed, it weighs 25.0 N and its coefficient of kinetic friction is 0.35 . Find the tension in the rope ?


Homework Equations


Fx = t - Fk
T = Fk = μk * N = μk *mg


The Attempt at a Solution


My answer results 85.84 N ... which is completely off the textbook answer 8.75 which can be yield by μk * m ... I don't understand why does it eliminate the 'g' out of the equation?
 
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Look at the units mentioned in the question.
 


Lol , thanks, i actually came back coz i found the answer and I knew it was something really stupid ...
 


No problem! Every year, the AP examiners' report mentions that many many points are lost because of units or calculation errors, so always check the units!
 
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