The work done in accelerating a ball to a certain speed

AI Thread Summary
To calculate the work done by a pitcher in accelerating a baseball to a speed of 95 mph, the mass of the baseball is 0.145 kg, and the final velocity is approximately 42.47 m/s. The discussion highlights the relationship between work and kinetic energy, noting that the work done is equivalent to the change in kinetic energy of the ball. Participants express confusion over using force and distance in the calculations, but clarify that the relevant equation involves kinetic energy. Ultimately, the focus is on determining the work done specifically for the acceleration of the ball. Understanding this relationship simplifies the problem-solving process.
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Homework Statement


The fastball of a famous pitcher in the National League has
been clocked in excess of 95 mph. Calculate the work done
by the pitcher in accelerating the ball to that speed. The
mass of a baseball is 0.145 kg.

mass = 0.145 kg
final velocity (in m/s) = 42.4688 m/s
initial velocity = 0 m/s

Homework Equations


F = ma
w = F*distance


The Attempt at a Solution


I tried setting up F = ma to find something, but the only known variable is mass. I also tried kinematics, but there are only two known variables that go into the equations and I can't isolate any variables. Is there an equation I'm forgetting, or am I just looking at this problem the wrong way? Thanks.
 
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How is work related to energy?
 
Ohhh, work is the change in energy. So the work done would just be the kinetic energy of the ball at the velocity?
 
He might very well have done some other work, but the question is specifically about work spent on accelerating the ball.
 
Okay got it, thanks!
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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