If the container filled with liquid gets accelerated horizontally or vertically, pressure…

If the container filled with liquid gets accelerated horizontally or vertically, pressure in liquids gets changed. In case of horizontally accelerated liquid (a_x), the free surface has the slope a_x/g. In case of vertically accelerated liquid (a_y) for calculation of pressure, effective g is used. A closed box with horizontal base 6 m by 6m and a height 2m is half filled with liquid. It is given constant horizontal acceleration g/2 and vertical downward acceleration g/2 .
Maximum value of water pressure in the box is equal to -