Acceleration Lab: Homework Statement Analysis

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    Acceleration Lab
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The discussion revolves around analyzing the velocity vs. time function derived from a cart rolling down an incline. The 'accepted value' for the velocity function is v(t) = 331t + 52, while the 'measured value' is v(t) = 326t + 41, leading to confusion over the correct interpretation of the coefficients. Participants express uncertainty regarding the meaning of 'a' in the context of acceleration and the accuracy of v(0), which is initially stated as 52 mm/s but later questioned for unit correctness. The conversation highlights a potential discrepancy in the experimental setup, suggesting that the launcher may not perform as predicted. Overall, the thread emphasizes the importance of correctly understanding the relationship between acceleration, velocity, and their respective units in physics experiments.
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Homework Statement



So basically we allowed a cart to role down an incline plane and we recorded the results with a ticker taper. Now there are a couple of questions that my teacher asked that I do not fully understand.

This entire section is a bit shady. I do not fully understand what the hell a represents?

Now, the actual velocity vs. time function should be (this was worked out with calculus):
v(t) = 331 t + 52 we'll call this the 'accepted value'
Remember that this is written in slope-intercept format, so the accepted values are:
a = ____________ mm/s v(0) = 52mm (accepted values)
Using the interval velocity vs. time graph, Excel worked out the velocity function as
v(t) = 326 t + 41 we'll call this the 'measured value'
Remember that this is written in slope-intercept format, so the measured values are:
a = ____________ mm/s v(0) = 41mm (measured values)
What should v(0) actually be? _______________
 
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I have no idea either, is it possible that the units are wrong and it is referring to the acceleration? You can tell that even though your acceleration is reasonably close, about a 2% fractional error by my mental math, that the value of v(0) is completely off, which probably indicates a launcher that launches different from what its predicted to do.
 
so would the acceleration just be the coefficient in front of the t (with possible wrong units?) Also, how would we indicate what the value of V(0) should be?
 
Yes, if a represents acceleration then it is the time derivative of velocity, and the coefficient in front of the t in this case. The value of v(0) is given to you as an accepted value, right? v(0) = 52mm/s. Ah man, I just noticed the units for v(0) are wrong too. Huh? Maybe metaphysics will provide the answer... *Click* Ums online has failed me for the last time.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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