The speed of sound in an ideal gas is given by the relationship v = γrtm√ , where r - the universal gas constant = 8.314 j/mol⋅k ; t - the absolute temperature; m - the molar mass of the gas in kg/mol ; and γ is a characteristic of the specific gas. for air, γ = 1.4. calculate the speed of sound in the air. assume that air is 20% oxygen and 80% nitrogen and the temperature of air is 293 k . express your answer to two significant figures and include the appropriate units.

part b

while camping, you record a thunderclap whose intensity is 10−2 w/m2 . the clap reaches you 3.0 s after a flash of lightning. assume that the thunder radiates spherically from its source. estimate the total acoustical power generated by the bolt of lightning. express your answer to two significant figures and include the appropriate units.

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

Acup of coffee sits on the dashboard of an automobile. the car goes around a sharp curve. even though you hold the cup still, coffee still splashes out. this can best be explained due to a) density. b) friction. c) gravity. d) inertia.

Acar drives toward the right over the top of a hill, as shown below. which arrow represents the centripetal acceleration? w x y z