Quoting from one of my beloved lecturer (Pn Kiran) that teaches English, "Jin Khang, do not assume! When you assume, you are making ASS of U and ME. "
If memory serves me well, the reason she ranted this sentence to me is probably because I like to use the word "assume, or I guess" in most of my daily conversations. After all, the "assume and I guess" works sort like a "get free of "responsibility jail" card ",
which basically means "hey, I don't know whether I've done that shit, even though I am quite sure I did it. And if shit happens, don't say I didn't warn you. Now go and double check this shit".
It's probably the worst mindset you could have when you are entrusted to some responsibility. But then again, never once I admitted that I am good in any administration/leadership kind of stuff...fine, you could say I 'm spineless...But then again, from what I had observed, administration/leadership skill doesn't matter much when it comes to choosing a leader. Because the majority always had the mindset "Hey this guy is cool/outspoken/weirdly weird enough to be our leader. So pick him as the group leader". And it explained why I was entrusted to some leadership role...twice, (because I fall into the "weirdly weird" category).
(*it doesn;t happen on the U. People are rational enough (or perhaps started to know what power-hungry is *)
And yeah, what I want to write again? Oh yeah, Puan Kiran... Yeah, I talked about how my lecturer, Pn Kiran, hated the element of assumption. But unfortunately she doesn't know, that my future career is related to engineering field. And after years of enrolling in an engineering course, I noticed one thing~ engineers love to make assumption (like how mathematician did~)
(that explains why Pn Kiran is stuck teaching instead of working in an engineering field, she hates assumption)
We engineers, in some (or lots) of cases, we love to make assumption like "assume this variable/effect is negligible, assume a steady state condition, assume this *constant* to be some constant value *number* , assume this item is isotropic and etc etc etc*
And things get even fun when you are told to make an "educated assumption", and your solution will be based on your assumption. Just yesterday, I was involved in solving some question that involves some scary geometry because a lot of shitty variable has to be accounted, and the final solution is getting awkward...until
the TA say "thickness is negligible in your calculation. Just include this fact in your assumption and you have a much simpler solution". Whee!
And so, I was thinking...If we could just make assumptions on these kind of questions~...(note, technicality incoming)
Problem 1-assume a negligible value
Given this piece of metal with these dimensions x length, y width and z height, with constant k(thermal conductivity), with difference of temperature (y). Find the heat conduction rate~
My assumption: Heat conduction rate in the above problem is assumed to be negligible
Answer: Zero
Justification: Often time, when we do engineering analysis, we have to omit some term (by making some engineering assumption), so that the algebra involved is much easier. Also, some term are omitted because they meant to illustrate some relationship between 2 variables. There might also be cases when a particular variable will involve you a lot of calculation, yet giving an answer that is close to zero. Or (maybe most of the time), they just want to save time printing and writing textbook, and the textbook writer hates calculus
Don't do this: Because when the question ask you to find x, you say x is negligible and proceed to give a zero as answer. This is like "hey, I am asking you whether you stole my money" and you answer "in this case, your money is negligible.......and proceed to say, zero is my answer"
Problem 2-assume a constant value
Given this piece of metal with these dimensions x length, y width and z height, with constant k(thermal conductivity), with difference of temperature (y). Find the heat conduction rate~
My assumption: I assume that heat conduction rate is a constant value of 1
Answer : 1
Justification: Sometimes, textbook knows that you have to solve a 3rd-4th order of differential equation, and thus, they provide you with some constant so that you could save some time and instead solving for things that really mattered
Don't do this: Because when question asked you to solve , they are asking you to SOLVE the answer, not ASSUMING the answer
Problem 3-assume a working conditionsGiven this piece of metal with these dimensions x length, y width and z height, with constant k(thermal conductivity), with difference of temperature (y). Assume the conduction rate to be TWO dimensional. Find net conduction rate on point (x,y)
My assumption: I assume that the conduction rate is ONE dimensional (f**k it, two dimensional type of question is hard)
Justification : One dimensional type of problem involves a simple plug in into formula work while two dimensional type of problem involves shitty differential equation stuff that gonna makes you bang the wall. Therefore, in most engineering condition, we love 1D heat analysis than 2D heat analysis, but sometimes, people had to go through some shitty 2D conduction rate calculation because an accurate answer is needed
Don't do this: Because you are basically changing the question
Problem 4 - Deriving a formula
Given this piece of metal with these dimensions x length, y width and z height, with constant k(thermal conductivity), with difference of temperature (y). Derive the formula for heat conduction rate
My assumption : Since I bring my textbook, I know what the formula is
Answer : (copy from textbook, skipping those derivation process)
Justification: There's always a lot of exam question asking you to derive formulas, while you are thinking 'WTF other engineers/mathematician had derived this thing before, found us the formula, and print it in textbook. (possibly getting some nobel prizes in the process)" So why did you want me to repeat this whole shit again! Well, deriving it, often or not, test whether you understand the working concept and algebra behind the formula, so that you won't end up as some engineer that only know how to memorize formula.
Don't do this: Because "deriving a formula IS NOT copying a formula"
Problem 5 - Reality, dude, reality!
In a circuit, a resistor of 5ohm is connected to a 6000Volts power source, find the current in resistor
My assumption: In reality , when you connect a high voltage power source to a low resistance resistor, the resistor is going to explode/fried...
Answer: 0, the resistor is fried
Justification: You might be true in trality case, but then again, how many textbook questions are based on reality ? They just want to train your problem solving skill
Don't do this: Because 1.)you are inferring how stupid the person that write the exam question, and 2.) you did not solve the question. Expect a mad professor to give you a fail grade because of that answer alone.
Problem 6- My answer is always right
Given this piece of metal with these dimensions x length, y width and z height, with constant k(thermal conductivity), with difference of temperature (y). Find the heat conduction rate~
Answer: My answer will be the correct solution
Justification: Ok, this is just not going to work
Don't do this: Unless you want to get a fail grade in your exam
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