True, a university student should be expected to know the volume of a sphere.
But sheesh, even my calculus textbook has a few pages of review material on algebra, trig, and geometry, and the last named includes the formulas for the volume and surface of a sphere. I’d be surprised if the CRC handbook, that bible to engineers and scientists, doesn’t also contain that formula, though you’d think that virtually all its target audience excelled at mathematics and presumably knows that formula. It wouldn’t have compromised the test, or the course, to give the formula.
I’ve both taken and taught a lot of physics, both for majors and non-majors, and I agree with the OP 100%. It would be one thing if these equations popped up on a homework assignment, but it’s not fair to have them on a timed test. Good tests should probe whether students learned the material presented in class, not penalize them for not having random equations in their memory. The professor made a shitty test, and is trying to blame the students for it.
The only equation I’d give him a pass on would be getting mass from volume and density, as that is more of a basic concept than an equation, i.e. if you know what density is, you can figure out the relationship.
On one hand, I really feel like suggesting that any college student who understands and can compare voting methods is obviously not afraid of math and should remember the volume of a sphere for Eris’s sake. It isn’t like you’re being asked to derive a general solution to a differential equation or something.
On the other hand, I’ve yet to see a math book that didn’t have the tables mentioned by Spectre of Pithecanthropus, and I am certain I’ve used them before even if I don’t actually remember using them.
I both sympathize with the OP and feel disgust at the education system. It’s a sphere. Sheesh.
I’ve been through…
Classical mechanics
Energy & Magnetism
Fluid Dynamics
Intro to Quantum Mechanics
Themodynamics
Quantum Mechanics (undergraduate, and next semestre graduate)
Calculus I, II and III
College-level linear algebra
Ordinary and Partial Differential Equations
You know what? I still have to look up some “basic” formulae, as do most of my fellow math geeks. It’s “basic” as in “easy to understand.” Not “basic” as in, “will never leave your mind, no matter how many years have passed since you’ve used it.”
I think you deserve full credit on the sections where you had the correct reasoning. Hope you feel better.
I’m a college student, and my B.A. Music major has required me to take a whole bunch of Gen. Ed. classes. I didn’t take astronomy because it counts as a natural science, which was the Gen. Ed. block I chose to cut out of my program. I’m just not a math/science person, and I can say I would be terribly pissed if a prof pulled something like that and told me that it was “so basic.” I last took geometry in 10th grade (~1998) and I don’t remember ever hearing the formula for finding the volume of a sphere. Area and circumference of a circle, yeah, sure, but volume of a sphere? Never. And if you want to blame that on my high school, so be it, whatever.
The point is that even if it’s something everyone did learn in high school, which is not necessarily the case, it’s not something you can expect everyone to remember, especially people who may despise math and not deal with math at all on any sort of regular basis. Also, considering the prevalence of non-traditional students these days (at least at my school), you could be dealing with people who haven’t had high school math in 20 or 30 years. You cannot expect people to remember things like that, even assuming they learned them in the first place. So yes, the prof was in the wrong. And you should definitely get partial if not full credit for the other parts of the question if you got them wrong because you used a wrong answer from the first part.
If the professor never presented that equation, or gave a hint that it should be learned, he was in the wrong to use it on a test. It reminds me of my introductory multivariable statistics class where the second test was a rather involved matrix theoretic proof. Loved that one.
You’ve heard the joke about the mathematician, the scientist and the engineer who all needed to know the volume of a red rubber ball?
The mathematician measured the diameter and derived a formula to calculate the volume.
The scientist used a graduated cylinder partially filled with water to calculate the volume of the ball. (Measured the volume of water, added the ball, measured again and subtracted the first volume from the second)
The engineer inspected the ball, found the serial number and went over to the Handbook of Red Rubber Balls and looked up the volume.
Just joining in with the voices of reason that agree with the OP. I’ve got a BS in Mechanical Engineering, which means I’ve had to take at least a little math in the course of my studies. I could tell you the formula for the area of a circle, rectangle or triangle, the volume of a cube (maybe even a rectangular solid!), but not the volume of a sphere. No way. That’s one of those formulas that made me keep my freshman calculus book throughout my collegiate career. To expect a non-science type person to know it is ludicrous.
Interestingly enough, i knew the equation, despite being a history major in college and a history grad student now. I didn’t know it because i’m smart, or because i’m particularly good at mathematics; i knew it because i have a strange facility for recalling such arcane, relatively unnecessary stuff as equations and quotations that i heard years ago.
There is one gentleman in his late 30s in my class, come back for a degree he never had to get when he first entered the work force. Good guy, I talk to him fairly often. He was still laboring over the test when I left. The argument would be more in my favor if there was more than just one outlier older student, but the point is still well taken.
If one thing is for certain, it is this: I’m not forgetting the volume of a sphere for a while now.
Don’t feel too bad, Only Mostly Dead. Yesterday I sat down to help my son with his math homework (adding and subtracting fractions with unlike denominomimater thingys) and had to spend a while fiddling around with a pencil and scratch paper before I could remember how to do it.
Lord help the boy when he gets to algebra. I sure as hell won’t be able to.
If you didn’t have an way of knowing beforehand that the equation for a sphere might be needed then i’d agree with you, having that in the exam was a little unfair. Even so i wouldn’t get too upset about it, normally the way these questions are marked is so you can get marks for what you know, and only be penalised once for things you don’t know. So in that three part question you’d be penalised one mark for not knowing the volume equation, but get marks for knowing how to calculate mass from volume. Then even though your numerical answers would be wrong in the two following parts, you’d still get full marks for them if your methods were correct.
However surely you must have had some sort in hint that that equation might come up? Eg in previous exam papers, practice questions, homework assignments etc?
Come to think of it, I probably didn’t learn the volume of the sphere in HS either. My HS geometry course was entirely plane geometry. I’m sure it was in my book, but I don’t remember ever using it.
Jesus, this is the pit people, we can’t let this assholery slide by!
So: Grey, fuck you very much, sir. It should be easy for you to calculate the volume of your ass with your head stuck in it.
I took the highest level of math offered at my high school (Calculus BC) and got the highest grade on the AP test (thus testing out of my entire university math requirement), majored in Sociology (so I took several stat classes) and then went to law school, and now people pay me more per hour to explain federal income tax law to them than I’d wager you make all day, and I don’t remember the formula for shit. It’d take me a while to figure out the surface area of a freakin’ triangle (oooh, one third base times height?–do I get a cookie, Grey? asshole).
And you know why? Because math for some reason is the exact opposite of a bicyce. You stop doing it for any length of time and it just leaves your head of its own accord.
So you can take your sanctimonious attitude and stuff it, pal.
