Work/Energy Conservation Problem w/ Initial Velocity

AI Thread Summary
An applied force of 10.0 N acts on a 0.50 kg mass with an initial speed of 2.00 m/s on a surface with a coefficient of friction of 0.40. The energy conservation equation used includes initial kinetic energy, work done by the applied force, and frictional energy loss. The calculated final speed was initially found to be 22.1 m/s, which was later corrected to 2.21 m/s, indicating a possible decimal error. The final answer aligns with the expected solution, suggesting the initial calculation was incorrect due to a misplacement of the decimal. The discussion highlights the importance of careful calculations in physics problems involving work and energy conservation.
Bread Boy
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Homework Statement


An applied force of 10.0N acts horizontally on a 0.50kg mass on a floor with the coefficient of friction being 0.40. If the object had an initial speed of 2.00 m/s, determine its speed at 15.0m.


Homework Equations


General Energy Conservation Formula
Ek(i) + Ep (i) + Einput(i) = Ek(f) + Ep(f) + Eoutput(f)


The Attempt at a Solution


1/2 * 0.5 * 2^2 + (10 * 15) = 1/2 * 0.5 * v^2 + ((0.4)(0.5)(9.8) * 15)
(hope I wrote it down correctly haha)
v = 22.1 m/s

Now I know the answer is supposed to be 2.21 m/s, but I have no idea how I ended up with what seems to be a decimal place in the wrong position. What gives?

Thanks in advance for the help!
 
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Your work--and your answer--looks fine to me.
 
So I was correct? The solution key must have been wrong then. Thanks a bunch!
 
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