question_answer

A thin U - tube sealed at one end consists of three bends of length \[l=250mm\] each, forming right angles. The vertical parts of the tube are filled with mercury to half the height. All of mercury can be displaced from the tube by heating slowly the gas in the sealed end of the tube, which is separated from the atmospheric air by mercury. Determine the work done (in joule) by the gas there by if the atmospheric pressure is \[{{P}_{0}}={{10}^{5}}\] Pa, the density of mercury is \[{{\rho }_{mer}}=13.6\times {{10}^{_{3}}}kg/{{m}^{3}}\], and the cross-sectional area of the tube is \[S=1c{{m}^{2}}.\]

Answer:

7.7