A cart supports a cubic tank filled with a liquid up to the top. The cart moves with a constant acceleration a in the horizontal direction. The tank is tightly closed. Assume that the lid does not exert any pressure on the liquid when in motion with uniform acceleration. The pressure at a point at a depth h and distance / from the front wall is:

The pressure P at point x in the sum of pressure P1 and P2 where P1 is the pressure due to gravity and P2 is the pressure necessary to impart an acceleration a to the column of water of length /. Pressure P2 acting on a column of length I and area of cross-section A gives it an acieration a in the horizontal direction.P2A = AldaP2 = ldaAs pressure is a scalar quantity, soP = P1+P2 = hdg + lda = d(hg + la)