On: Navy Sets World Record With Rail Gun

[bigiain]

If you take the numbers from the article as accurate, 33 megejoules at Mach 7 means the weight is ~15kg (assuming I got all my conversions and orders of magnitude right, feel free to do your own e=1/2mv^2 calculation...)

[aidenn0 → bigiain]

I got ~10kg from the 2500m/s number, and under 12kg from the Mach 7 number. Google agrees:

http://www.google.com/search?q=2*33megajoules/(2500+m/s)^2+i...

http://www.google.com/search?q=2*33megajoules/(7+*+speed+of+...

[borism → bigiain]

Projectile speed will be much less after it has travelled 100km.