Is This Calculator Incorrect for Predicting Impact Force of a Falling Object?

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The calculator in question appears to only consider the stopping force after a falling object encounters a surface, neglecting the continuous influence of gravity during the fall. It is suggested that the stopping distance should be included in the height measurement to accurately calculate impact force. For example, using a mass of 50kg and a height of 10m with a stopping distance of 5m results in a calculated force of 1480N, while the calculator outputs 980N. This discrepancy arises because the calculator's assumptions may not apply when the stopping distance is significant compared to the height. Clarification of the calculator's caveat regarding height and stopping distance is essential for accurate predictions.
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I believe that this calculator generates answers assuming that the only force acting on a falling object after it has encountered a stopping surface is the force of the stopping surface. The calculator needs to factor in gravity throughout the whole fall. Would someone else please verify?
http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
Click Mechanics, work-energy principle, and then impact force of falling object, and "Since you know velocity, mass, and kinetic energy, can you predict the force of impact?"
Example numbers:
m=50kg, h=10m, d=5m
stopping force should be about 1480N, but the calculator is saying 980N.
 
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Read the little note at the bottom of that page.

Note that the above calculation of impact force is accurate only if the height h includes the stopping distance, since the process of penetration is further decreasing its gravitational potential energy.

That should take care of your problem (you probably should use d=5, h=5 to describe the situation I think you have in mind). If not for this disclaimer, the calculation would be, as you point out, wrong for the general case where d is not necessarily small compared to h.
 
I didn't take time to read that disclaimer carefully. Thanks for the quick answer!
 
It is not a disclaimer, it is a caveat. :mad:
 
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