What is the speed with kinetic energy

AI Thread Summary
To find the speed of a 0.145 kg baseball with a kinetic energy of 105 J, the kinetic energy formula is applied: KE = 1/2mv². The calculation leads to the equation 105 = 0.0725v², resulting in a speed of approximately 36.06 m/s. Participants suggest rechecking arithmetic and using a calculator to verify the result, as the online assignment provides immediate feedback on correctness. It is recommended to plug the calculated speed back into the kinetic energy equation to check for potential errors. Ensuring accuracy in calculations is crucial for confirming the correct speed.
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Homework Statement


What is the speed of a 0.145 kg baseball if it's kinetic energy is 105 J? Answer units in of m/s


Homework Equations


kinetic energy = 1/2mv^2


The Attempt at a Solution


105= 1/2(0.145)v^2
105= .0725v^2
v= 36.06
 
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What seems to be the problem? I would check that arithmetic again, with a calculator if possible.
 
Agreed, check your numbers.
 
Well it's an online assignment so it imediantly tells me if i am right or wrong... I did it with a calculator several times... What am I doing wrong?
 
Use your answer, plug it back into the KE equation, and tell us what you get. You might find a 10 percent error.
 
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