Question

Torricelli's barometer used mercury but Pascal duplicated it using French wine of density 989 kgm${}^{-3}$. in that case, the height of the wine column for normal atmospheric pressure is (Take the density of mercury =13.6 x 10${}^3$ kg m${}^{-3}$)

• A. 5.5 m
• B. 10.5 m
• C. 9.8 m
• D. 15 m

Answer 1

Answer: (B)

10.5 m

As $P=h\rho g$
Height of mercury column in Torricelli's barometer
$=0.76mofHg,$
${\rho }_{mercury}=13.6\times {10}^{3}kg{m}^{-3}$
${\rho }_{frenchwine}=984kg{m}^{-3}$

or $0.76\times (13.6\times 10m^3)\times 9.8=h\times 984\times 9.8$

or $h=\frac{0.76\times 13.6\times 10m^3\times 9.8}{984\times 9.8}=10.5m$