# Solenoid Kinetic Energy

I found this solenoid on Sparkfun (https://www.sparkfun.com/datasheets/Robotics/ZHO-1364S-36A13.pdf) and according to the datasheet it is able to provide a force between 36N and 5N depending on the current travel position (see page 3). I approximated this in an excel sheet, calculating the accelleration of a mass that is being pushed by the soleniod: $$a=F/m$$ $$v^2=2*a*s$$ $$E_{kin}=1/2*m*v^2$$ Somehow, these values seem to be way too high when compared to an traditional, spring-loaded system where I would get around 3 Joule out of an 200N spring. Is there an mistake in my calculation? I have a feeling that it might have something to do with the speed the solenoid itself is moving.

• Your graph shows force max at a little over "30" and force min at a little below "5". This seems to tally with the data sheet so, what is the issue here? – Andy aka Jul 27 '17 at 11:51
• @Andyaka The problem is that the energy is unbelievably high. – mxcd Jul 27 '17 at 12:06
• I suppose you either believe the data sheet or you don't. Perhaps you'd have more confidence if you bought from a mechanical supplier, and had broad tables to select from, – Scott Seidman Jul 27 '17 at 12:20
• Your second equation looks wrong. Do your dimensional analysis to convince yourself the units on both sides don't match up. This isn't electrical engineering BTW – Scott Seidman Jul 27 '17 at 12:35
• Why don't you just use the area under the force-distance graph to compute the kinetic energy directly? – Jon Jul 27 '17 at 13:21