Physics · MECHANICAL PROPERTIES OF FLUIDS

An open-tube mercury manometer (\( \rho = 13.6 \times 10^3\text{ kg/m}^3 \)) is connected to a gas container. Initially, the mercury level in the atmospheric arm is \( 15\text{ cm} \) higher than that in the arm connected to the gas. Atmospheric pressure is \( 1.010 \times 10^5\text{ Pa} \). The gas is then heated until its absolute pressure increases to \( 1.418 \times 10^5\text{ Pa} \). Taking \( g = 10\text{ m/s}^2 \), the new difference in heights between the mercury levels in the two arms is:

1. A
   \( 30\text{ cm} \)
2. B
   \( 25\text{ cm} \)
3. C
   \( 45\text{ cm} \)
4. D
   \( 20\text{ cm} \)