Average force exerted on a baseball

AI Thread Summary
To calculate the average force exerted on a baseball during contact with a bat, the initial momentum of the baseball is determined to be 5.075 kg*m/s. The contact time is given as 0.50 milliseconds, which is clarified to be 0.5 x 10^-3 seconds. The discussion emphasizes the importance of understanding SI prefixes in physics calculations. Participants confirm that the time unit is not a typo but a standard notation. This highlights the need for clarity in unit interpretation when solving physics problems.
vaibzzz123
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1. Question
A 0.145kg baseball moving horizontally at 35.0m/s strikes a bat and is popped straight up to a height of 55.6m before turning around. If the contact time is 0.50ms, calculate the average force on the ball during the contact.

Homework Equations


p=mv
Δp=mΔv=fΔt
Ek=0.5mv^2 (?)
Ep=mgh (?)

The Attempt at a Solution


pinitial=(35)(.145)=5.075 kg*m/s

I was going to use the time that was given, but I'm unsure if the "ms" unit was a typo or was written on purpose. If it was on purpose, I'm unsure how I should use it
 
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Why do you think it is a typo? What do you think "ms" means? Are you familiar with the SI prefixes?
 
Orodruin said:
Why do you think it is a typo? What do you think "ms" means? Are you familiar with the SI prefixes?
Ah, didn't realize that it meant milliseconds! First time I've ever seen that in Physics. Would that mean 0.50ms=0.5*10^-3s or 5*10^-4s?
 
vaibzzz123 said:
Would that mean 0.50ms=0.5*10^-3s?
Yes.

vaibzzz123 said:
Ah, didn't realize that it meant milliseconds! First time I've ever seen that in Physics.
The SI prefixes may be used together with any unit in the SI system. It is a good lesson to take in.

Edit: The caveat being the use together with the SI unit kg ...
 
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