The tyre pressure of a car was found to be 150cmHg in the morning at a temperature of 27°C. Hard driving in the afternoon raised the temperature of the tyres to 57°C. The tyre pressure by the afternoon would be?

A.

increased by 15.0cm Hg

B.

decreased by 15.0cm Hg

C.

increased by 22.50cm

D.

decreased by 22.50cm Hg

E.

remained constant

Correct answer is A

\(\frac{P_1}{T_1}\) = \(\frac{P_2}{T_2}\) at constant volume

\(\frac{150}{27 + 273}\) = \(\frac{P_1}{57 + 273}\)

P2 = 165cmHg