Hello Ayush
All the courses are based on pure mathematics and simple logics of physics. The subject, however, does get pretty advanced as you go deeper into it.
Now regarding jobs after B.Tech in mechanical: there are plenty. As long as men depend on machines, mechanichis will be in demand. However, most of them is non core (even the 10Lpa PSUs).
In India B.Tech Mechanchis are more or less labourers albeit with better salaries.
Or if not that, mere supervisors who should keep their technical knowledge at home.
As a result, a large chunk of mechanchis have to follow one of these paths:
1) Get a job in core technical (As I said a rarity with only a B.Tech, maybe <1%)
2) Get a job in public sector (IES, PSUs, Central & State Govt.)
3) Go abroad in one of the best universities & pursue research
4) Go for IAS
5) Bell the CAT (MBA)
6) Open the GATE for M.Tech
7) Join the Indian Army, Navy or Air Force
8) Go abroad in ordinary college/university in countries with easier immigration laws (Aus, Canada) and try getting a permanent job & PR.
Candidates can check B.Tech Cut off for Top IITs & NITs here.
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