Pipelines are cleaned by pushing through them a close-fitting cylinder called a pig. the name comes from the squealing noise it makes sliding along. suppose the pig diameter is 0.149 m and its length 0.6 m. it cleans a 0.15-m-diameter pipe at a speed of 1.2 m/s. if the clearance is filled with glycerin at 20°c, what pressure difference, in pascals, is needed to drive the pig? assume a linear velocity profile in the oil and neglect air drag,

Refrigerant-134a enters the compressor of a refrigerator as superheated vapor at 0.14 mpa and -10°c at a rate of 0.05 ka/s and leaves at 0.8 mpa and 50°c. the refrigerant is cooied in the condenser to 0.72 mpa and 26'c. it is then throttled to 0.15 mpa. sketch the t-s diagram for the system and evaluate: 6) the rate of heat removai from the refrigerated space (kw), it) the power input to the compressor (kw), ii) the isentropic efficiency of the compressor (%), and iv) the cop of the refrigerator.