In the given figure the container slides down with acceleration `a` on an incline of angle B liquid is station any with respect to container find out .
(i). Angle made by surface of liquid with horizontal plane.
(ii). Angle if `a=gsintheta`

Explanation

Consider a fluid particle on surface. The forces acting on it are shown in figure ltBrgt Resultant force acting on liquid surface will always normal to it `tanalpha=(macostheta)/(mg-masintheta)=(acostheta)/((g-asintheta))`
thus angle of liquid surface with the horizontal is equal to `alpha=tan^(-1)((acostheta)/(gcos^(2)theta))` ltbr (ii) if `a=gsintheta`, then `alpha=tan^(-1)=tan^(-1)((acostheta)/(g-gsin^(2)theta))=tan^(-1)((gsinthetacostheta)/(gcos^(2)theta)`
`=tan^(-1)(tantheta)`
`alpha=theta`