Hi Ethan -- I'd love to see pics of your rail gun when it's finished -- maybe you could write an article to share with us here on EEWEb.com.Regarding your question, let's start by noting that:#1 Force = mass x acceleration#2 Energy = force x distance#3 1 joule = 1 Newton x 1 Meter
The amount of energy that a capacitor delivers is given by: Jc = (1/2 x Vi^2 x C) – (1/2 x Vf^2 x C)
Where C is the capacitance value, Vi is the starting voltage, Jc is the energy from the capacitor, and Vf is the ending voltage.The capacitor probably won’t discharge all the way to zero volts, hence the Vf portion of the equation above.Energy is in joules (J) during the discharge, where J = watts x seconds, or J= instantaneous voltage x instantaneous current x seconds.The mass of the projectile comes into play to figure the energy required. After the required energy (Jc) has been determined, choose C, Vi, and Vf to meet the Jc formula above (f there are significant losses in the rails and the rig in general, increase Jc to account for this).Over to you
