Calculate the Speed of a Baseball with Mass 145g and Kinetic Energy 122 J

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To calculate the speed of a baseball with a mass of 145g and kinetic energy of 122 J, the kinetic energy formula, KE = 0.5 * m * v^2, is used. Rearranging the formula to solve for speed (v) involves isolating v, which results in v = sqrt(2 * KE / m). Substituting the values, the mass must be converted to kilograms, leading to the calculation of speed. The discussion highlights confusion among participants on how to apply the formula effectively. Understanding the relationship between mass, kinetic energy, and speed is crucial for solving the problem.
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Homework Statement



A pitcher throws a baseball toward home plate. The baseball, which has a mass of 145g, approaches the plate with 122 J of kinetic energy. Calculate the speed of the baseball.

Homework Equations





The Attempt at a Solution

 
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njohnson222 said:

Homework Equations





The Attempt at a Solution


*ahem*

so what about it?
 
ummm, how do u figuar it out? We are stumped. I am trying to show a grade 10er how to do this. I don't know this stuff or how to figuare it out.
 
njohnson222 said:
ummm, how do u figuar it out? We are stumped. I am trying to show a grade 10er how to do this. I don't know this stuff or how to figuare it out.

it has 122J of kinetic energy, what is the formula for kinetic energy?
 

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