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New World Record: Most Powerful Railgun

December 11, 2010 Leave a comment

As opposed to a traditional gun, which uses a small explosion to propel a projectile at a target, a railgun uses and electromagnetic field.

If you can generate a strong enough magnetic field, the resulting force can hurl a projectile at unprecedented speeds and energies.

What a navy ship can do is pulse a large amount of electricity through two rails. This generates a huge magnetic field. The resulting magnetic force, called the Lorentz Force, is what accelerates the projectile.

This is a video I saw at Scientific American showing the old world record, which was set in 2008 with an energy of 10 megajoules.

A joule is a unit of energy. A megajoule is a million joules. To put that kind of energy in perspective, a typical 9mm bullet weights about 115 g. If you were to give that bullet 10 megajoules of energy, it would travel at a speed of over 13 kilometers per second! Thats about 8 miles per second!

Now, this new railgun can reach energies of 33 megajoules, a three-fold improvement. Here is the video for the new record which was set yesterday.

The railguns will be able to fire a projectile hundreds of miles at an average speed of roughly Mach 5, or 5 times the speed of sound. The advantages of using railguns means carrying dangerous chemical weapons are unneccessary, as well as being able to fire smaller weapons from a large distance.