Consider a planet with a radius of 4,000 km. moons of the same density as the planet will break up if their orbits move within what distance of the planets center?
a. 2,400 km
b. 4,800 km
c. 9,600 km
d. 19,200 km

The air in an automobile tire with a volume of 2.60 ft3 is at 70°f and 21 psig. determine the amount of air that must be added to raise the pressure to the recommended value of 30 psig. assume the atmospheric pressure to be 14.6 psia and the temperature and the volume to remain constant. the gas constant of air is ru = 53.34ft⋅lbflbm⋅r(1 psia144 lbf/ft2) = 0.3704 psia⋅ft3lbm⋅r the amount of air that must be added to raise the pressure is lbm