In the communicating vessels there is mercury of what height the water column needs to be added

In the communicating vessels there is mercury of what height the water column needs to be added to one of the tube elbows so that the mercury levels shift from the initial position by 2 cm.

To calculate the required height of the poured water column, we use the equality: ρw * hw = ρp * hr, whence hw = ρp * hr / ρw = ρr * 2 * hsm / ρw.

Data: ρр – density of mercury (ρр = 13.6 * 10 ^ 3 kg / m3); hcm – displacement of each of the mercury levels (hcm = 2 cm); ρw is the density of water (ρw = 10 ^ 63 kg / m3).

Calculation: hv = 13.6 * 10 ^ 3 * 2 * 2/10 ^ 3 = 54.4 cm.

Answer: It is necessary to add a 54.4 cm high water column to one of the tube bends.