Which of the following is true about the regions on the either sides of the contact surface inside a shock tube?

A)
Both regions have same temperature and pressure but different velocity
B)
Both regions have same velocity and pressure but may have different density and temperature
C)
Both regions have same density and pressure but different temperature
D)
Both regions have same temperature and density but may have different velocity and pressure

Correct Answer :   Both regions have same velocity and pressure but may have different density and temperature


Explanation : On the either side of the contact surface, the temperature and density may be different but it is necessary that the pressure and fluid velocity be the same, since contact surface is an imaginary boundary which separates high pressure gases from mixing with low pressure gases.