Torricelli's barometer used mercury. Pascal duplicated it using French wine of density $984 ext{ kg

Question

Torricelli's barometer used mercury. Pascal duplicated it using French wine of density $984	ext{ kg/m}^3$. What is the approximate required height of the wine column to measure normal atmospheric pressure ($1.013 	imes 10^5	ext{ Pa}$)? ($g = 9.8	ext{ m/s}^2$)

Professor PC Thomas Classes · Answer

Atmospheric pressure balances the hydrostatic pressure of the fluid column: $P = ho gh \implies h = \frac{P}{ho g} = \frac{1.013 	imes 10^5}{984 	imes 9.8} = \frac{101300}{9643.2} \approx 10.5	ext{ m}$.