A tank containing water up to a depth of 650 mm is stationary. Find the force exerted by fluid of specific gravity 0.55 on the side of tank, width of tank is 1.5m. Ρ water = 1000 kg/m³:

Engines for propeller-driven aircraft are limited in their maximum rotational speed by the fact that the tip speed of the propeller must not approach the speed of sound in air (mach i). taking 6 ft as a typical diameter for a propeller of a light airplane and 1100 fils as the speed of sound, find the upper limit on the rpm (revolutions per minute) of the propeller shaft.