In an experiment to find the coefficient of real expansion of Hg, 70cm coloumn of Hg at 00C  is found to balance 71.26c, coloumn of Hg at  1000C. γR of mercury is  n×10−6/0C where n=

coefficient of real expansion of liquid is γR=h2−h1h1Δt h2=71.26cm,h1=70cm are heights of liquid in manometer; Δt=100 is change in temperature γR=71.26−7070×100 γR=1.2670×100=0.18×10−3 γR=180×10−6 ∴n=180