The edge of the sun doesn’t have to be absolutely sharp in order to look that way to us. it just has to go from being transparent to being completely opaque in a distance that is smaller than your eye can resolve. remember from astronomical instruments that the ability to resolve detail depends on the size of the telescope’s aperture. the pupil of your eye is very small relative to the size of a telescope and therefore is very limited in the amount of detail you can see. in fact, your eye cannot see details that are smaller than 1/30 of the diameter of the sun (about 1 arcminute). nearly all the light from the sun emerges from a layer that is only about 400 km thick. what fraction is this of the diameter of the sun? how does this compare with the ability of the human eye to resolve detail? suppose we could see light emerging directly from a layer that was 300,000 km thick. would the sun appear to have a sharp edge?

The lights used by mark watley (played by matt damon) during the film the martian seem to be metal halide lamps. metal halide lamps are filled with vaporized mercury and metal-halogen compounds. when an electric current is passed through the lamp, the tube begins to glow a bright white/blue color. if you were to pass this light through a prism to separate the individual light frequencies, you would see a rainbow just as you would if using natural sunlight because of the complexity of the metal halide gas and the vast amount of possible electron transitions. (the study of light in this way is known as spectroscopy and allows astronomers to know exactly what atoms compose distant stars, simply by looking at the light they emit. the spectral lines an atom produces uniquely identifies that atom just like a fingerprint uniquely identifies a person. the momentum equation and energy equation that we have used above can be combined to give the following equation: c = e p where again p is the phonon momentum, e is the photon energy and c is the speed of light. when you divide the photon energy found in #6 by the photon momentum found in #4, do you get the speed of light? (if not, check your work for questions #4 through #6). yes no

What is the momentum of a 2 kg object moving at 15 meters per second

Because light travels in a straight line and casts a shadow, isaac newton hypothesized that light is