Maintenance awarded cannot be punitive. It should aid the applicant to live in a similar life style she/he enjoyed in the matrimonial home. It should not expose the non applicant to unjust contempt or other coercive proceedings. On the other hand, maintenance should not be so low so as to make the order meaningless.
You have two liabilities, first maintain your wife and take full care of your child. From the various judicial precedents, these 11 factors which are to be taken into consideration while deciding alimony :-
1. Status of the parties.
2. Reasonable wants of the claimant.
3. The independent income and property of the claimant.
4. The number of persons, the non applicant has to maintain.
5. The amount should aid the applicant to live in a similar life style as he/she enjoyed in the matrimonial home.
6. Non-applicant's liabilities, if any.
7. Provisions for food, clothing, shelter, education, medical attendance and treatment etc. of the applicant, additional maintenance for child ( if any).
8. Payment capacity of the non applicant.
9. Some guess work is not ruled out while estimating the income of the non applicant when all the sources or correct sources are not disclosed.
10. The non applicant to defray the cost of litigation.
11. The amount awarded under Section 125 Cr.PC is adjustable against the amount awarded under Section 24 of the Act.
So it is discretion of the court to decide appropriate alimony. It would be 15-20 k per month.