I speak from experience...you will use some of the fundamentals from your engineering classes on the job, but for the most part you'll never see any of it again and will learn your skills on the job. I remember my first week of my first engineering job, I tried to use this really complex analysis method for vapor-liquid equilibrium, because it was what we had been taught in school for this particular scenario. When I told a more experienced engineer what I was doing, he looked at me like I was crazy and said "The heck is all this junk? Just assume ideal gas, it's probably close enough!" I was like wow, there goes 2 or 3 classes of material out the window lol.
Now back to the actual topic, I went back to school recently and it is a challenge managing work and fun in engineering. However I have been putting in a lot of effort, and managing to go out on a handful of dates and outings with friends. It just takes good time management, which happens to be one of my strong points. I'll often see people going nights with no sleep while I have no issues at all, simply because I manage my time so well. I will just say, that I would recommend trying to use your time in college as best you can. I found out my first time through that once you get out, socializing and meeting people becomes infinitely harder. Most people in the work force, particularly in engineering, will be in their 40s or older with families, so it can be really difficult to meet younger people. At my last job I was the only person out of 100+ employees under 35, and all but a handful were married, so it was hard to really do much with them outside of work. So I would recommend trying your best to work on developing social skills, and asking women out, because in my opinion it only gets harder once you graduate.
That said do not neglect your studies, as those should be your first and foremost priority. If they start to suffer at all, then focus as much attention as is needed on them to ensure that you do well. Your grades stay with you for a long time, so it's best to get them right while you can
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