268) An ordinary passenger aircraft requires a cooling system of capacity.

269) In air-conditioning of aeroplanes, using air as a refrigerant, the cycle used is

270) The thermal diffusivity for solids is generally less than those for liquids and gases.

271) Conduction is the process of heat transfer from one particle of the body to another by the actual motion of the heated particles.

272) Moisture should be removed from refrigerants to avoid