What is the Correct Way to Calculate Average Force of Impulse?

AI Thread Summary
The discussion revolves around calculating the average force of impulse when a baseball is hit, with specific parameters provided. The user attempts to apply the impulse-momentum equation, FΔt = mΔv, and calculates a force of 374.3 N, but receives feedback that the answer is incorrect. Despite confidence in the understanding of the equation, the user struggles with the online system's feedback, suspecting it may be unreliable. Other participants affirm the user's grasp of the physics involved, suggesting that the issue may lie with the online platform rather than the calculations themselves. The conversation highlights the challenges of using online homework systems for physics problems.
Psych Berry
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I can't seem to master this equation, because I think I'm doing things right and I'm not.

Homework Statement


When a 410 baseball gram is hit, its velocity changes from +28.87 m/s to -22.34 m/s. The baseball is in contact with the bat for 56.10 milliseconds. You may assume that the balls outward velocity is antiparallel to its incoming velocity.

What is the magnitude of the average force on the ball?


Homework Equations


FΔt = mΔv


The Attempt at a Solution


(0.410 kg)(-22.34 m/s - 28.87 m/s)/(0.0561 s) = F
374.3 N = F
But this isn't correct.

I messed up Δv before, did I do it again?
 
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Looks OK to me. Why do you say it's wrong?
 
Doc Al said:
Looks OK to me. Why do you say it's wrong?

It's an online pre-assignment, said my answer was incorrect. I tried playing around with sig figs and signs (in case the question forgot it's supposed to be magnitude), but I've tried 5 times and haven't been able to get it correct.
 
Those online systems can be flaky. But there's nothing wrong with your understanding of that impulse-momentum equation.
 
Doc Al said:
Those online systems can be flaky. But there's nothing wrong with your understanding of that impulse-momentum equation.

That's definitely true, thanks! I for sure trust your physics judgment over the program's.
 

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