hi sir my friend got 49800 rank in ts emcet medical rank 2018 she belongs to SC category is she get free seat in government college

First of all, understand the fact that the concept of free seat implies that you are supposed to pay a nominal amount of fees. 100% exemption from paying fees is definitely out of question.
Secondly, the cut off ranks for seat allotment change every year, a clear picture will be obtained after the counseling procedure commences.

With SC category, your friend can get medical college in 2nd counselling.