A pheromone is a type of volatile compound produced by a variety of insect species for chemical communication. These molecules can be used to signal alarm, to attract a mate, or to indicate the presence of food. The presence of 1.20 × 10⁻⁸ g of a pheromone can be sensed by another insect within a radius of 0.500 miles. Calculate the density of this pheromone. (1609 m = 1 mile) Assume that the area that a pheromone can be sensed is a cylindrical air space. Calculate the volume of this air space assuming a radius of 0.500 mi and a height of 40.0 ft.

What is the density of the black hole

Hot air balloons float in the air because of the difference in density between cold and hot air. in this problem, you will estimate the minimum temperature the gas inside the balloon needs to be, for it to take off. to do this, use the following variables and make these assumptions: the combined weight of the pilot basket together with that of the balloon fabric and other equipment is w. the volume of the hot air inside the balloon when it is inflated is v. the absolute temperature of the hot air at the bottom of the balloon is th (where th> tc). the absolute temperature of the cold air outside the balloon is tc and its density is ďc. the balloon is open at the bottom, so that the pressure inside and outside the balloon is the same. as always, treat air as an ideal gas. use g for the magnitude of the acceleration due to gravity.

The fact that the total amount of energy in a system remains constant is a(n)