Pure tone sound waves are sinusoidal oscillations of the density of air. our model of waves on an elastic string (beads and massive strings) suggests that waves of moving matter depend on a restoring force (like a tension) and inertia (like a mass), we expect that the speed of sound in air should depend on the air pressure, p (normally about 100 kpa) and the density of the air, rho (normally about 1 kg/m3).part (a) using dimensional analysis, propose an equation for the speed of sound in air using only the parameters p and p. a 17%
part (b) since our dimensional analysis can't tell us if there are numerical factors like 2 or n in our formula, we can't be sure that it provides a good result. calculate what speed of sound your formula predicts. give your answer in m/s. a 17%
part (c) compare your result from part (b) to the real speed of sound. how well does the formula created by dimensional analysis do?

Imagine that someone pushes one marble toward a motionless marble. would there still be action-reaction forces involved in the collision? how might the marbles’ motions be changed? ?

Aheat engine running backward is called a refrigerator if its purpose is to extract heat from a cold reservoir. the same engine running backward is called a heat pump if its purpose is to exhaust warm air into the hot reservoir. heat pumps are widely used for home heating. you can think of a heat pump as a refrigerator that is cooling the already cold outdoors and, with its exhaust heat qh, warming the indoors. perhaps this seems a little silly, but consider the following. electricity can be directly used to heat a home by passing an electric current through a heating coil. this is a direct, 100% conversion of work to heat. that is, 19.0 \rm kw of electric power (generated by doing work at the rate 19.0 kj/s at the power plant) produces heat energy inside the home at a rate of 19.0 kj/s. suppose that the neighbor's home has a heat pump with a coefficient of performance of 4.00, a realistic value. note: with a refrigerator, "what you get" is heat removed. but with a heat pump, "what you get" is heat delivered. so the coefficient of performance of a heat pump is k=qh/win. an average price for electricity is about 40 mj per dollar. a furnace or heat pump will run typically 200 hours per month during the winter. what does one month's heating cost in the home with a 16.0 kw electric heater? what does one month's heating cost in the home of a neighbor who uses a heat pump to provide the same amount of heating?

An object resting on a table weighs 100 n. with what force is the object pushing on the table? with what force is the table pushing on the object? explain how you got your answer.