Answer:
(a) 11.437 psia
(b) 13.963 psia
Explanation:
The pressure exerted by a fluid can be estimated by multiplying the density of the fluid, acceleration due to gravity and the depth of the fluid. To determine the fluid density, we have:
fluid density = specific gravity * density of water = 1.25 * 62.4 lbm/ft^3 = 78 lbm/ft^3
height = 28 in * (1 ft/12 in) = 2.33 ft
acceleration due to gravity = 32.174 ft/s^2
The change in pressure = fluid density*acceleration due to gravity*height = 78*32.174*(28/12) = 5855.668 lbm*ft/(s^2 * ft^2) = 5855.668 lbf/ft^2
The we convert from lbf/ft^2 to psi:
(5855.668/32.174)*0.00694 psi = 1.263 psi
(a) pressure = atmospheric pressure - change in pressure = 12.7 - 1.263 = 11.437 psia
(b) pressure = atmospheric pressure + change in pressure = 12.7 + 1.263 = 13.963 psia
