Estimate the smallest possible period of a satellite in a circular orbit around earth. (mass and radius of earth is 5.98 x 1024 kg and 6.37 x 106 m. the universal gravitational constant g = 6.67 x 10-11 n. m2/kg2 .)

An insulated 40 ft^3 rigid tank contains air at 50 psia and 120°f. a valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 25 psia. the air temperature during this process is kept constant by an electric resistance heater placed in the tank. determine the electrical work done during this process.

Conventional hot-water heaters consist of a tank of water maintained at a fixed temperature. the hot water is to be used when needed. the drawback is that energy is wasted because the tank loses heat when it is not in use, and you can run out of hot water if you use too much. some utility companies are encouraging the use of on-demand water heaters (also known as flash heaters), which consist of heating units to heat the water as you use it. no water tank is involved, so no heat is wasted. a typical household shower flow rate is 2.50 gal/min (9.46 l/min ) with the tap water being heated from 51.0 ˚f (10.6 ˚c) to 120 ˚f (48.9 ˚c) by the on-demand heater. what rate of heat input (either electrical of from gas) is required to operate such a unit, assuming that all the heat goes into the water?

Two lasers are shining on a double slit, with slit separation d. laser 1 has a wavelength of d/20, whereas laser 2 has a wavelength of d/15. the lasers produce separate interference patterns on a screen a distance 5.30 m away from the slits. part a which laser has its first maximum closer to the central maximum? view available hint(s) which laser has its first maximum closer to the central maximum? laser 1 laser 2