A 1 hp motor is used for running a dual cylinder reciprocating compressor of a refrigeration system based on $\mathrm{R}-134$ a refrigerant having $185 \mathrm{~kJ} \mathrm{~kg}^{-1}$ cooling capacity. COP of the system is 4.2 and overall efficiency of the compressor is $80 \%$. Specific volume of the refrigerant vapour at suction temperature is $0.15 \mathrm{~m}^{3} \mathrm{~kg}^{-1}$. The compressor with bore diameters of $40 \mathrm{~mm}$ each runs at $1440 \mathrm{rpm}$.The compressor stroke length in $\mathrm{mm}$ is

(A) 16.8

(B) 33.7

(C) 50.5

(D) 67.4

A 1 hp motor is used for running a dual cylinder reciprocating compressor of a refrigeration system based on $\mathrm{R}-134$ a refrigerant having $185 \mathrm{~kJ} \mathrm{~kg}^{-1}$ cooling capacity. COP of the system is 4.2 and overall efficiency of the compressor is $80 \%$. Specific volume of the refrigerant vapour at suction temperature is $0.15 \mathrm{~m}^{3} \mathrm{~kg}^{-1}$. The compressor with bore diameters of $40 \mathrm{~mm}$ each runs at $1440 \mathrm{rpm}$.The compressor stroke length in $\mathrm{mm}$ is

(A) 16.8

(B) 33.7

(C) 50.5

(D) 67.4

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