Yes, mechanical engineering is difficult, ashok_nanjundi. But to paraphrase the signature of another user on CR4, "If it was easy, anybody could do it".
Do you have a specific question about mechanical engineering?
What is to be refer to have the specific material identification ( identification by eye sight) and how to understand the material sturcture without radiography/microstructure analysis. please explaine the radio graphy and microstructure reading and understanding.
To be honest: before we had radiography we had no clue on the internal structure of metals and the difference between some alloy's. There is now way that you can explain the behavior of metals on eyesight.
Don't think that mechanical engineering is a closed book: it still has uncompleted pages and whole chapters to be generated.
But perhaps you have to learn to walk before running, that is how we all started.
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"Here we are now, entertain us"
Nothing vague about mechanical engineering. Engineering is all about using the known laws of physics to make something of utility. Any subject requires considerable study to master it. Mechanical engineering is no different. For those who like machines it is a most rewarding field of study.