Water flows steadily into and out of a tank that sits on frictionlesswheels as shown in Fig. P5.60. Determine the diameter Dso that the tank remains motionless if F = 0.
Air Quality Dispersion and deposition o Airflow patterns Temperature inversion Warm air forms above cold air, trapping pollutants near ground Height of emission Time in atmosphere Warm air is above the cold air Troposphere: lowest layer Stratosphere: second Mesosphere Thermosphere Ionosphere Exosphere Pollution n troposphere o Acid rain comes from nitric oxide and sulfur dioxide released from electric power plants and motor vehicles o Heavy metal pollution o Before 1920, smelters were primary source of atmospheric pollution o After 1930, they added lead into the fuel and that increased lead emissions hugely o The 1970 clean air act required that lead be removed Pollution in stratosphere o No direct effect for human health o Can influence climate Aerosols can cool earth’s surface o Alter sunlight reaching earth’s surface o Destroying the ozone CFC (chlorofluorocarbon) Indoor air pollution o More polluted than outside air o Tobacco smoke, building materials, furniture, ovens, etc. etc. etc. o Combustion byproducts Carbon monoxide, nitrogen and sulfur oxides, VOCs, particulate matter Indoor burning, second h and smoke