. Find the efficiency of a motor vehicle engine if at a speed of 45km/ h the engine consumes 12litres of petrol per 100km and develops a power of 16hp . The density of the petrol is 3 0.8g / cm . The heat value of petrol is 45kJ / g

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.