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
Verified Correct Answer: C.
Physical Principles & Numerical Solution
\(\frac{V_1P_1}{T_1} = \frac{V_2P_2}{T_2}\)
\(\frac{1 \times 30}{527 + 2733} = \frac{5P_2}{127 + 273}\)
\(\frac{30}{800} = \frac{5p_2}{400}\)
P2 = \(\frac{400 \times 30}{800 \times 5}\)
= 3
Source: Myschool Past Questions Archive (Record #33580)