Problem 08 - Variation of Pressure

Note: Absolute pressures are sometimes measured in atmospheres. Example: 1 atmosphere = 14.7 psi absolute and 2.7 atmosphere = 39.69 psi absolute.
 

$p_1 = \text{pressure on the surface}$

$p_1 = 0.4(14.7) = 5.88 \, \text{ psi absolute}$

$p_1 = 5.88 - 14.7 = -8.82 \, \text{ psi gage}$
 

$p_2 = \text{pressure at 4 ft below the surface}$

$p_2 = p_1 + \gamma h = -8.82 + 1.5(62.4)(4)\left( \dfrac{1}{24^2} \right)$

$p_2 = -6.22 \, \text{ psi}$           answer