How to convert Joules(kinetic energy) plot chart into watts? Anyone know how?enter image description here

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    $\begingroup$ Watts are Joules per second, so area under the curve. $\endgroup$ – Solar Mike Oct 4 '18 at 3:24
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    $\begingroup$ @SolarMike But the area under the curve would give Joules times seconds, which seems a meaningless quantity. Using the slope of the curve would be better! $\endgroup$ – alephzero Oct 4 '18 at 8:28
  • $\begingroup$ Why you don't plot it in Watts? Solidworks does plot in Watts. $\endgroup$ – Sam Farjamirad Oct 4 '18 at 10:31
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    $\begingroup$ @SolarMike I think you're thinking of the other way around. To get total energy from a power plot you just integrate. $\endgroup$ – JMac Oct 4 '18 at 14:36
  • $\begingroup$ Yeah; the differential is tan( angle of the curve ) or rise rate. $\endgroup$ – SF. Oct 5 '18 at 12:33

To convert a plot of J versus s to a plot of J/s vs s, take the derivative.

Here is my quick-and-dirty answer after digitizing the data.

derivative plot

  • $\begingroup$ What software package[s] did you use here? $\endgroup$ – Chemomechanics Oct 4 '18 at 22:23
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    $\begingroup$ IgorThief in Igor Pro. WaveMetrics.com. When I would have the raw data rather than image, this would be a direct one-step process that would be accurate rather than rough. $\endgroup$ – Jeffrey J Weimer Oct 4 '18 at 22:51
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    $\begingroup$ @Chemomechanics my favorite tool for digitizing graphs is DataThief. It's like magic. $\endgroup$ – Carl Witthoft Oct 5 '18 at 16:53

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