Pressure
A cylindrical beaker of cross-sectional area A A\,A contains a liquid of mass MMM. The beaker is placed in an elevator that is accelerating vertically upwards at a constant rate aaa. The atmospheric pressure acting on the open top surface of the liquid is p0p_0p0, and the acceleration of free fall is ggg.
Which expression correctly represents the absolute pressure p p\,p exerted on the bottom of the beaker?
p=p0+M(g+a)Ap = p_0 + \frac{M(g + a)}{A}p=p0+AM(g+a)
p=p0+M(g−a)Ap = p_0 + \frac{M(g - a)}{A}p=p0+AM(g−a)
p=p0+MgAp = p_0 + \frac{Mg}{A}p=p0+AMg
p=p0−M(g+a)Ap = p_0 - \frac{M(g + a)}{A}p=p0−AM(g+a)