Any teacher of elementary physics can attest to the waning interest of students when all they are exposed to are boxes sliding down planes. In an effort to motivate interest, it is often useful to borrow examples from the real world. This way the students find it easy to identify the relevance of the subject matter. In addition, high-tech applications can be inspirational and serve to motivate the students to look deeper into the phenomena. One example of a technology that makes students sit up and pay attention are railguns. They are easily demonstrated using YouTube videos, especially now that the U.S. Navy has begun to release publicity videos of their latest designs and associated fact sheet and papers. This paper gives some background and simple models of the relevant physics of railguns.

1.
US NAVY 5,600 mph RAILGUN – Navy’s Gigantic Electromagnetic Railgun Is Ready for Deployment
,” YouTube, https://www.youtube.com/watch?v=9PItPL7EZEc.
2.
U.S. Navy Demonstrates World’s Most Powerful Electromagnetic Railgun at 10 MJ
,” Office of Naval Research, https://www.onr.navy.mil/media-center/fact-sheets/electromagnetic-railgun.aspx.
3.
I. R.
McNab
,
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Stefani
,
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Crawford
,
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Erengil
,
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Persad
,
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,
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Vanicek
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, and
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