I am in USA now on tourist visa upto July 27th, I got urgent work in India, can I go n come for 15 days?

Just because you were given until July 27 on your entry does not mean that you are allowed to come back to be in the US for another 15 days after returning from India. Your leaving and coming back subjects you to a new inspection when your return. A CBP officer may wonder why he or she should allow you to come back in after such a short trip outside the country. You may have a more sympathetic inspection if you are able to outline the reasons for which you need the additional time and you are able to produce documents relating to the urgency of your having to return to India before being able to accomplish your original purpose in the US. Due to the limitations of the Lawyers.com Forums, Alan Lee & Arthur Lee, Esqs.’ (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.