A glass tube `80 cm` long and open ends is half immersed in mercury. Then the top of the tube is closed and it is taken out of the mercury. A column of murcury `20 cm` long then remains in the tube. The atmospheric (in cm of Hg) is
(assume temperature to be constant )

A narrow uniform glass tube 80 cm long and open at both ends is half immersed in mercurry. Then the top of the tube is closed and it is taken out of mercury. A column of mercury 22 cm long then remains in the tube. What is the atmospheric pressure?

A tube 1.5 m long and closed at on end is half filled with mercry and is then inverted with its open ends just dipping into a mercury tough.Find the height of mercury in the tube if the reading of the barometer is 0.75 m.

A U shaped tube has two arms of equal cross section and lengths l_(1) = 80 cm and l_(2) = 40 cm. The open ends are sealed with air in the tube at a pressure of 80 cm of mercury. Some mercury is now introduced in the tube through a stopcock connected at the bottom (the air is not allowed to leak out). In steady condition the length of mercury column in the shorter arm was found to be 10 cm. Find the length of the mercury column in the longer arm. Neglect the volume of the part of the tube connecting two arms and assume that the temperature is constant.