Calculating velocity in regards to the mass and kinetic energy of an object

AI Thread Summary
To calculate the velocity of a baseball with a mass of 145 g and 94 J of kinetic energy, the correct mass in kilograms is 0.145 kg, not 0.0145 kg. The formula used is v = √(2Ek/m), which leads to the calculation v = √(2 * 94 J / 0.145 kg). This results in a velocity of approximately 36 m/s, aligning with the book's answer. The confusion arose from using the incorrect mass value in the calculation.
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Homework Statement



How fast is a baseball with a mass of 145 g traveling if it has 94 J of kinetic energy?

Homework Equations



m = 145 g or 0.0145 kg
Ek = 94 J
v = ?

v = √2Ek/m

The Attempt at a Solution



I get...
v = √2(94)/0.0145 kg
v = √12966
v = 114

But my book says it should be 36 m/s. What am I doing wrong?

It also mentions that I need to recall that 1 J = 1 kg . m^2/s^2 but I am unsure how to incorporate this into the equation or if it is even necessary.
 
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Your mass should be .145 kg.
 
Your mass should be 0.145 kg and not 0.0145kg
 
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