16 April 2014
If you offering this income under the head Capital gain then required to pay tax @15%+edu.cess on profit u/s 111A, Because of short term capital on equity shares is taxable at special rate u/s 111A is 15% irrespective of the taxable income. In addition to this tax you also liable for interest u/s 234B,C and u/s234A(if return not file with in due date u/s 139(1)).
However you are saying your trading is interday trading means there is frequency of transactions and they may be settle on the same day also,so we can considered it as business and profit or loss on such trading shall considered as business income. So if you offering it under the head income from business then you need not to pay any tax because of such profit of Rs.40000 shall include as your normal taxable income and for A.Y 2014-15 basic exemption limit to tax is Rs.200000 and in addition to this there is tax rebate upto Rs.2000 u/s 87A if total income of the individual assessee doesn't exceeds Rs.5,00,000.
So if you offering it under the head capital gain then should be pay tax @15% on Rs.40,000 + E.cess+interest if any otherwise offering under business head then no need to pay tax.
02 October 2021
Intraday transaction are not assessed under Capital Gain; but are speculative business transactions, assessed under head PGBP. In your case there is no tax liability, after rebate; so you must file return. (ITR2)