Ask Us General Physics

By NASA.


List of topics:

Basic Physics Questions  
Particle Physics
Mass
Spectra
Antimatter
Storing Antimatter
When Matter and Antimatter Collide
Carbon-14
Sub-divide Electrons?
Atoms and Empty Space
Plasma
Quarks
Leptons
Muons
Latest on Neutrinos
Charge of Neutrinos
Gamma Ray Momentum
Coordinates of Time and Space
Evaporation
Compression of Matter
Momentum and Center of Mass
Is It Density?
Scale and Balance
Speed and Friction
Accelerometers
Entropy and Potential Energy
Gravity - Definition of a "G"  
Speed of Gravity  
The Cause of Gravity  
Why Does the Universe Have Gravity?  
Does Gravity Increase as Mass Increases?
Does Gravity Affect Height?
Reflect Gravity?
Light Affected by Gravity?
Where is Zero G?  
Build a Chamber with Zero G?  
Jumping Up in a Falling Elevator  
Why Can't I Feel the Earth Turning?  
Escape Velocity  
Free-falling
Physics and Skydiving
Falling Boxes
Falling in a Vacuum
The Casimir Force
Speed and Velocity
If Hens Inside a Van Fly...
Motion is Relative
Special Relativity: Ball on a Train
Instantaneous Velocity
Acceleration of a Baseball?
Hunter and Monkey
Motion Inside a Moving Train
Speed of Light
Effect of Mass on Speed of Light?
Speed of Light Slowed?
Speed of Light Constant
Rotation and the Speed of Light
Why Not Faster Than the Speed of Light?
Speed of Light vs Speed of Sound
Speed of Sound - Underwater
Cerenkov Light
Time Near the Speed of Light
Time
Properties of Light
Motion of Light
Doppler Shift of Light
Spectrum of Visible Light
Color, Sunlight, and Energy
Color and Isaac Newton
How Are Rainbows Formed?
Index of Refraction
Light in a Cone-Shaped Prism
Why Do Things Get Smaller When Farther Away?
Electromagnetic Spectrum and Pair Production
Difference Between Emission and Absorbtion
Lines of Emission and Absorbtion of Light
Light in a Box
Spectroscopes
Wave Height
Wave-Particle Duality
Does Everything Have Wave-like Motion?
Radio Waves
Secondary Mirror in a Telescope
Using Mirrors to Melt Snow
Free Electrons Absorb Light?
Electron Volts
Elastic Potential Energy
Kelvin Convention
Absolute Zero
Fusion
Cold Fusion
Compass and Magnetic Poles
Magnetic Fields
Magnetic Field Lines
Reversing a Magnetic Field
Magnetic Fields and Light
Motion and Magnetic Fields
Two Magnets
Magnets and Heat
Electromagnets
Magnetic Fields Harmful?
Magnetic Shielding
Propagation of Gravitational and Electromagnetic Fields
Energy Cannot Be Created or Destroyed
Grand Unified Theory
String Theory
Size and Scale
More on Size and Scale
Catalysts
Silica and Radiation
How Does a Spacecraft Dissipate Heat?
Laser Basics
Lasers: Energy and Matter
Lasers and Color
Are Atoms in Photons?
Charge of Photons
Spooky Particles
Radiation
Radiometer
Make a Light Saber?

Make a Light Saber? How do you make a real light saber like those in the Star Wars movies? There is no way to make a light saber. To a physicist, a light saber looks like a square wave of light, but it would require a nearly infinite combination of wavelengths and a very high energy density, and we just don't have any way to generate that. Then could I use plasma to make the blade? You would have to have some way of containing the plasma, or it would just dissipate. A strong magnetic field would do it, but even if you could generate the properly shaped magnetic "bottle" external to the light saber handle, the magnetic bottle would interact with matter (walls and such) in a way that light sabers don't. Plus the light sabers would give off a tremendous amount of heat that wouldn't be stopped by the magnetic bottle. A light saber is fiction and will be for the foreseeable future.

Sorry, Wedge!

Man, I could easily waste all day browsing around that site.

(Backing slowly away from the computer.)

Yes, just a few days around here and you can absolutely FILL your head with useless imformation. learn some shit occasionally too, not in this thread mind you.. but it can be done.

Quoted: Make a Light Saber? How do you make a real light saber like those in the Star Wars movies? There is no way to make a light saber. To a physicist, a light saber looks like a square wave of light, but it would require a nearly infinite combination of wavelengths and a very high energy density, and we just don't have any way to generate that. Then could I use plasma to make the blade? You would have to have some way of containing the plasma, or it would just dissipate. A strong magnetic field would do it, but even if you could generate the properly shaped magnetic "bottle" external to the light saber handle, the magnetic bottle would interact with matter (walls and such) in a way that light sabers don't. Plus the light sabers would give off a tremendous amount of heat that wouldn't be stopped by the magnetic bottle. A light saber is fiction and will be for the foreseeable future. Sorry, Wedge!

Even rocket surgeons can be stupid. You can buy light sabers at Wal Mart for crap sakes.