Help with Displacement vs. time and acceleration

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SUMMARY

The discussion centers on analyzing the displacement vs. time graph of a ball dropped from rest, represented by the quadratic regression equation -4.03x^2 - 2.06x + 1.20 with an R^2 value of 0.99857. The user seeks guidance on creating a velocity vs. time graph using the kinematic equation h(t) = (1/2)At^2 + V0t + h0. It is emphasized that since the ball is dropped from rest, the coefficient of the linear term (V0) must be zero, necessitating a revision of the regression to ensure accurate fitting of the parameters.

PREREQUISITES
  • Understanding of quadratic regression analysis
  • Familiarity with kinematic equations in physics
  • Knowledge of graphing techniques for velocity and displacement
  • Basic skills in interpreting R-squared values for model accuracy
NEXT STEPS
  • Redo the quadratic regression with the constraint that V0 = 0
  • Learn how to derive velocity from displacement using calculus
  • Research the relationship between acceleration and displacement in free fall
  • Explore graphing tools for visualizing kinematic equations
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Students studying physics, particularly those focusing on kinematics, as well as educators looking for practical examples of graphing displacement and velocity relationships.

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Homework Statement



I have the following points that were gathered from a displacement vs. time graph (the graph is of a ball being dropped from rest). The line is parabolic. The quadratic regression for the points is [tex]-4.03x^2-2.06x+1.20[/tex] where [tex]R^2=0.99857[/tex].

Correct me if I'm wrong but the quadratic regression is the same as this: [tex]h(t)= \frac {1}{2}At^2+V_{0}t+h_{0}[/tex]

I need to make a velocity vs. time graph with this information but I need a little guidance.

(time (s), displacement (m))
(0.000, 1.194)
(0.097, 0.979)
(0.129, 0.881)
(0.161, 0.774)
(0.193, 0.654)
(0.258, 0.399)
(0.290, 0.254)
(0.322, 0.102)
(0.354, 0.000)


Homework Equations


[tex]h(t)= \frac {1}{2}At^2+V_{0}t+h_{0}[/tex]


The Attempt at a Solution


I performed the quadratic regression but now I'm stuck
 
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Think of x as representing time t, then match whatever constants you found from your quadratic regression to the constants in the kinematic equation that you quoted. But (and this is a big "but") if the ball was dropped from rest, then the linear term in t must have its coefficient constrained to be zero for a meaningful fit (i.e. v0=0). I think you need to redo your regression with that in mind. You should be able to predict from the kinematic equation what the fitted parameters ought to be and then verify that they are what you expected.
 

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