which one is better electrical eng. at iit bombay or computer science at iit kanpur?

Hi..
Both IIT Bombay and IIT Kanpur are among the top colleges and no doubt that are both very good. It actually depens on your interest now. If you are compassionate about any one particular branch out of the two, you should go for that because in the long run you will have to be there with that branch.
Take the decission wisely.
All the best.
Regards