A difference In density between gases creates buoyancy which is the ability of an object to float. 0°C helium has a density of .18 kg/m³. 0°C regular air has a density Of 1.29 kg/m^3.
In kilograms how much mask in a cubic meter of helium float in regular air at 0°C?

Acommercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°c by rejecting waste heat to cooling water that enters the condenser at 18°c at a rate of 0.25 kg/s and leaves at 26°c. the refrigerant enters the condenser at 1.2 mpa and 50°c. if the compressor consumes 3.3 kw of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load, (c) the cop, and (d) the minimum power input to the compressor for the same refrigeration load.

Acorporation gives out its profits as dividends paid to whom?

How long will it take a car traveling of a constant speed of 45m/s to cover the distance of a 2.5km?