Hi Vishal,
The amounts on balance account are moved to the same account during opening.
The amounts on a P&L account will be moved to the 'year-end result' or specified opening account during closing.
If you take the trial balance from the system at the end of the fiscal year and run a P&L, you should be able to see earnings for the current year which is expected to be transferred to the opening account for P&L type accounts.
Regards
Rahul Mohta
Independent Advisor for Microsoft Dynamics AX