Numerical on Mercury Barometer | Numerical using atmospheric pressure formula

Question 1) The density of mercury is 1.36 × 10⁴ kg m^–3. Calculate the length that a mercury barometer will have when the atmospheric pressure is 101 kPa.

Answer 1) Rearranging the atmospheric pressure equation related to Mercury Barometer gives the expression for the length of mercury:

Atmospheric Pressure P = Δhρg
=> Δh = P/(ρg) ……………………….. (equation 1)

Given: density of mercury = ρ= 1.36 × 10⁴ kg m^–3
Atmospheric Pressure P = 101 kPa = 101 × 10³ Pa
g = 9.8 m/s²

From Equation 1:
Δh = P/(ρg) = (101 × 10³) / (1.36 × 10⁴ x 9.8) = 0.76 m