In the air, the amount of work done is equal to 4 If the lifting cable of a hoist lifts a 250-lb engine
times 250 lb, or 1,000 foot-pounds of work.
Select one:
O A.5
O B.2
O C.3
O D.4

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.