Q7: Pascal duplicated barometer using a fluid of density 1000 kg/m3, as the working liquid (see Figure below). What was the height h of fluid column for normal atmospheric pressure? Would you expect the vacuum above the column to be as good as for mercury?
Q8: A Ping-Pong ball has a diameter of 0.038 m and average density of 0.084 0 g/cm3. What force is required to hold it completely submerged under water?
Q9: A piece of aluminum with mass 1.00 kg and density 2 700 kg/m3 is suspended from a string and then completely immersed in a container of water (see Figure below). Calculate the tension in the string (a) before and (b) after the metal is immersed.