A ball of relative density 0.8 falls into water from a height of 2m. The depth to which the ball will sink (neglect viscus force)

Velocity with which it hits the water surface   2g.2m/sNet force inside mg-vd1g. F=mg−mdldsgF=mg1−10.8=−mg4 So it moves down with retardation g/4.Stopping distance  v22a=2.g 22.g/4=8m