Hi,
The difference between both programmes is of stream , ba psychology is pursued by arts students and bsc psychology is pursued by science students.
Moreover ba psychology is oriented towards liberal arts with less technical and science while bsc psychology is more related to science with focus on  maths and statistics.
Ba psychology is good for students who want to go for counseling,  education  , social work , journalism   while bsc psychology  is for students who wish to enter medical profession or go for research.
Hope it helps...