Air at temperature 527oC and pressure 30 atmospheres is admitted into the cylinder of an engine. Calculate the pressure of the gas when it has expanded to 5 times its volume and cooled to 127oC as it leaves the engine
-
A.
1.5 atmospheres -
B.
2.5 atmospheres -
C.
3.0 atmospheres -
D.
12.8 atmospheres -
E.
15.0 atmospheres
Correct Answer: Option C
Explanation
(frac{V_1P_1}{T_1} = frac{V_2P_2}{T_2})
(frac{1 times 30}{527 + 2733} = frac{5P_2}{127 + 273})
(frac{30}{800} = frac{5p_2}{400})
P2 = (frac{400 times 30}{800 times 5})
= 3