Fundamental Physical Constants
Coefficients of Friction
Indices Of Refraction
Nuclear & Particle Data
Special Math Constants
Calculators & Apps
Periodic Table of Elements
Time Reference & Exact Time
Humidex & Windchill Calculator
Decimal Multiples & Prefixes
Materials Safety Info
Nobel Prize & Bruce Medal Info
Electricity & Magnetism
Waves in Matter, Sound
Light, Optics and Photonics
Atomic & Nuclear
Special & General Relativity
Astronomy & Astrophysics
Definitions & Reference
All Answers, all categories
University and College Departments
Institutes and National Labs
History of Physics
Reference for Educators
Cartoons by Rick London
Cartoons by Mark Parisi
Cartoons by John McPherson
Cartoons by Jerry Van Amerongen
Solvay ala PhysLink.com
Jokes, jokes and more jokes
Chemist's equiVALENT Party
Is there Santa?
'Twas The Night Before Christmas, NASA-style
The Fate of the Universe
The Ten Commandments for Amateur Astronomers
Ask the Experts - Optics
How does night vision work?
What are the light bullets (electromagnetic solitonss)? Do they contradict the Maxwell equations?
What would a bubble of air or an air lens in water do to parallel incoming rays of light?
What is the Zeeman effect?
How do we know that the light from a distant, moving source has shifted from one part of the spectrum to another?
How does a laser cool something, as in producing a Bose-Einstein condensate?
Why can you not get sunburned behind a glass?
Would I receive more energy from a solar cell if I were to filter everything but UltraViolet light? Or do you get more energy from all wavelengths added together?
If I were able to set a flashlight out in the middle of space and turned it on, would it move?
Why do colors illuminated with moonlight lack color?
If you stand at the bottom of a well and look up at the entrance is it possible to see stars in daylight?
Why is it dangerous to look at the solar eclipse directly specially at that moment?
What causes different colors in flames?
What is material dispersion? In which way it is helpful in optical communication?
How do liquid crystal displays (LCDs) work?
How does sunblock block out UVa and UVb rays?
Is it possible to slow light down?
Why do colors illuminated with moonlight lack color?
Why don't photons collide with each other when traveling towards each other?
Why does your hand look funny when you move it fast in front of the tv or computer screen?
What is Huygen's Principle?
Why is petrol/oil in water colorful?
Why does the passenger side window on my car state 'objects in mirror are closer than they appear?
Is it possible for a single photon to produce diffraction pattern?
How is the frequency of a photon/light measured? How long does such a measurement take?
How do diffraction gratings tell us information about distant stars and galaxies?
What is the mirage effect?
Can you make an ultra-violet light source by painting a regular incandescent light bulb with black paint?
What is the equivalent of 1 Lux unit in Watts?
If a spherical mirror is immersed in water, does its focal length change?
What is the coherence length? What is the coherence time?
How fast a person must be going in a car to make a red light appear green?
What happens at the ends of the electromagnetic spectrum? Do the wavelengths continue to get shorter and longer or is there some ultimate limit?
How night vision goggles work?
How do we see things upright if the image formed on the retina in our eye is an inverted one?
How is light formed in a light bulb?
The index of refraction for liquid water is 1.33. What is the index of refraction for ice? The physical density is changed, but is the optical density changed as well?
Why are there no stars when the astronauts take pictures from space?
What are liquid crystals made of?
What is the wavelength of UVa, UVb, and UVc light measured in nanometers, and frequency (in Hz)?
Why the planets are not twinkling, while the stars are?
What is a one way mirror and how does it work?
Why does the red color appear at the horizon during sunset?
What are Lambert's Laws?
How are solar sails possible? If photons have no mass, how can they push on something?
Why are the colors of the sky at sunrise different at sunset?
How could you direct the laser towards the transparent tank full of water so that 100% of the laser light was reflected?
Why are sunsets red?
Is there any way to see ultra violet light, or make it?
When high velocity particles travel faster than the speed of light in a medium they create a blue flash. This is called Cerenkov Radiation, why does this happen and why is it blue?
Why does light slow down when entering a prism but speed up when it exits? Where does it get the energy to increase it's velocity?
Why are reflected images seen more easily at night in a window from inside of the house, whereas during the day they are not?
Why does dispersion take place when light is passed through prism and not through glass slab?
My science data book says that the mass of a photon is zero. But how can photon exert radiation pressure, as it occurs in the sun?
Theoretically would light infinately bounce, in a room made of perfect mirrors?
Why is there no colour spectrum at the sub-atomic level? Or is there?
If you were to design a laser, how would you determine the wavelength of light that would be produced?
What is the formula to find the absorption coefficients of materials?
When an electron tunnels from one place to another, does in happen instantaneously, or does it require a finite amount of time? Can things other than electrons tunnel?
How is the photon energy related to photon frequency?
Is it possible for a patch of light to travel faster than the speed of light?
Why does sound wave travel faster in a denser medium whereas light travels slower?
Why is a light colored T-shirt cooler to wear than a dark colored T-shirt?
Why can we see the sunlight for over 20 minutes even after sunset?
How tall does a mirror have to be to fit an entire persons body?
Which makes more sense: that photons [and other quantum objects] are neither waves nor particles or that they both waves and particles?
How long does it take the sun's light to reach earth?
I was told that uv rays can not go thru glass but can go thru quartz. Is that true?
I got a speeding ticket and the cop told me he used a laser gun on me or the car in front of me. How does it work? I would like to fight the ticket.
When you look at a spoon why is your reflection upside down?
I know why the sky is blue during the day, and why it turns yellowish to reddish at sunrise and sunset. My question is; why doesn't the sky ever look green? Why does the color go from blue to yellow?
What is the Photoelectric Effect?
If, indeed, the speed of light is constant,why is it usually listed for a vacuum?
How was the speed of light determined and who found it, when? How close was the estimate of 186,000 mps to the 'actual' speed of light?
In movies why do wheels of a moving car appear to rotate backwards to the actual direction?
Would not the speed of a light beam headed toward a black hole increase tremendously? We do know it could be bent by the gravity of a star.
What determines the color of large bodies of water (i.e. Ocean/large lakes?)
What would light be like if there was no ability for light to make a rainbow?
What are the wavelengths of the basic colors (Red, Orange, Yellow, Green, Blue, Violet) in the color spectrum?
'Where the telescope ends, the microscope begins. Which of the two has the grander view?'
© Copyright 1995-2020 PhysLink.com