Hello
avtar31193 , An Indian Postal Order is a useful way of sending and receiving small amounts of money from / to any corner of India. An Indian Postal Order can be used only for making RTI payment to a Central Government Department.

In case of Government of India, the prescribed application fee is Rs. 10/- which can be paid through a demand draft or a banker's cheque or an Indian Postal Order payable to the Accounts Officer of the public authority.

So,yes you can use 50 rupees indian postal order.

Hope it will be helpful for you :)

Fee for Seeking Information

In case of Government of India, the prescribed application fee is Rs. 10/- which can be paid through a demand draft or a banker's cheque or an Indian Postal Order payable to the Accounts Officer of the public authority.