In physics and engineering, in particular fluid dynamics and hydrometry, the volumetric flow rate, (also known as volume flow rate, rate of fluid flow or volume velocity) is the volume of fluid which passes per unit time; usually represented by the symbol Q (sometimes VÌ). The SI unit is m3/s (cubic metres per second).
The symptoms of the disease were black and purple spots on the body. The spots soon began to become enlarged and swollen. The victims were taken captive by death in about two to seven days. The plague lasted for four years, but it still remained a recurrent fear until the seventeenth century.
The bacteria that caused the Black Death, which wiped out millions in mid-14th century Europe, may be extinct, according to a new study. Hoping to resolve some controversy regarding the cause of the Black Death, researchers examined more than 100 samples taken from bodies buried in London during that time.