An unknown mineral is scratched by a penny. it must a: be talc b: have a mohs hardness of 10 c: be softer than a diamond d: have perfect cleavage

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

3. on your graph, the data points between the black squares are data for elements with atomic numbers 3 through 9. locate these elements on your periodic table. what term or description would you use to identify these elements with respect to the periodic table?

In a load, the load is paralel to the shaft. n a. angular n b. thrust n c radial n d. none of the above