hi,

see there is decent job opportunities after completing b.sc, however if you want to work in teaching position or want to do phd or work as a research fellow you should go for msc course. there is decent placement available in iits for students who are pursuing msc from iits.

however after completing b.sc in physics you may work as a teacher in private school, may work as a office assistant, laboratory assistant, or may prepare for government exams of bank, ssc etc.

hope it would help.