Whenever you suppose of Star Wars, you consider lightsabers. Proper? What could possibly be higher, from a movie-making standpoint, than a futuristic sword that allows you to create superior fencing duels like in old-time Errol Flynn swashbucklers. (So a lot better than watching Stormtroopers fireplace their blasters into partitions and ceilings and the rest besides their targets.)
Lightsabers are available a cosmic rainbow of hues (color-coded blue or inexperienced for good guys, pink for dangerous) and quite a lot of shapes. There’s even a double-bladed model in Phantom Menace. (I don’t need to begin a nerd combat—but—however the perfect lightsaber battle within the canon must be the “Duel of the Fates” in that film, because of the talents and scariness of Darth Maul actor Ray Park.)
So … precisely what are lightsabers? In fact, they aren’t actual, so no one actually is aware of how they work. Even the characters within the motion pictures appear just a little confused about it. In Phantom Menace, Anakin calls it a “laser sword.” Yeah, he was a child, however each Din Djarin (the Mandalorian) and Luke Skywalker additionally consult with it as a laser sword—although I think Luke was being sarcastic.
Anyway, that’s simply unsuitable: It might probably’t be a laser. For starters, lasers beams are invisible from the aspect, so that you wouldn’t see a factor until you staged the duels in a disco with fog machines to scatter the beams. Second, the beams go on endlessly; they don’t have an finish. Third, laser beams can’t clank collectively like swords—they’d simply go by means of one another once you attempt to parry.
However what’s it then? We will tremendously slim the chances by asking if the blade has mass. If it’s some type of gentle (as you’d suppose from the identify “lightsaber”), then the reply isn’t any—gentle, or electromagnetic radiation, has no mass. If we will decide that it has mass, then it’s not gentle.
It is a query we can reply, by analyzing how lightsabers transfer once you wave them round. In different phrases, it’s time for some physics!
Mass and Movement
Don’t confuse mass and weight. Mass is a measure of how a lot “stuff” like protons, neutrons, and electrons are in an object, and weight is the quantity of gravitational drive performing on an object. Right here we need to see what impression the mass of a lightsaber would have on its movement. However let’s begin with one thing less complicated.
As a substitute of a lightsaber, say now we have a “lightball” fabricated from the identical buzzy substance. Because it’s symmetrical, we will describe its movement with out worrying about rotation. If we need to transfer this ball forwards and backwards, we name on Newton’s second legislation of movement. This says the acceleration (a) of an object is dependent upon its mass (m) and the quantity of drive (F) utilized to it.
