Question

Toricelli’s barometer used mercury. Pascal duplicated it using French wine of density 984 kg m–3. Determine the height of the wine column for normal atmospheric pressure.

Answer 1

10.5 m Density of mercury, ρ1 = 13.6 × 10 3 kg / m3
Height of the mercury column, h1 = 0.76 m
Density of French wine, ρ2 = 984 kg/m3
Height of the French wine column = h2
Acceleration due to gravity, g = 9.8 m/s2
The pressure in both the columns is equal, i.e.,
Pressure in the mercury column = Pressure in the French wine column
ρ1h1g = ρ2h2g
$h_2 = \frac{ρ_1h_1 }{ ρ_2}$

$=\frac{ 13.6 × 10 3 × 0.76 }{ 984 }$

= 10.5 m
Hence, the height of the French wine column for normal atmospheric pressure is 10.5 m.