Hi all, Background: I'm working on a project where I am dropping an arduino with an accelerometer from ~100 ft in the air to measure it's acceleration during free fall and at impact. I need to compare my collected data with predicted models. I have the model for free fall (just 9.8m/s^2), but I'm struggling to find a model equation for acceleration at impact. Perhaps I am overthinking this... Attempt: The best equation I have found is "The Rate of Deceleration Formula" which is: So this will give me a constant. I need to plot this model with my actual data that I collect. However, the units of deceleration are in m/s^2, and if I multiply this value by time, I will get a velocity. Question: Is the model for acceleration at impact a constant (whatever value the rate of deceleration turns out to be) and I am just intuitively wrong here? If it is not, do you know of a good model to use? If it is a constant, that would mean that I'd intuitively expect the acceleration to nearly reach the model's rate of deceleration value before dramatically decreasing to 0 (as it settles on the ground).