What to do if your professor is not much ''intelligent''?

[Headacheguy]

Our Physics I midterm exam papers were returned to us this afternoon. One question had been answered wrong by our prof, unfortunately.

It was a simple vector question where the gravity is referenced as positive and thus downward acceleration should be positive as well, however she insisted that it is negative because it is going ''down''.

We tried many times to explain how she got it wrong but she just won't see it, I can tell that she was very much annoyed. Sadly, that question was worth 10/70 of the test.

I learned that our professor has only a BS in Chemical Engineering, and she's teaching general physics.

Should I just let it pass?

 

[ZapperZ]

Ask another physics instructor to verify what is correct.

Zz.

 

[Fizex]

I would go to another physics professor, confirm the problem, and ask without being annoying if the prof. can get it straight with yours.

Edit: Didn't see ZapperZ's post, oh well.

 

[eri]

Yes, talk to another professor. Then see if you can figure out why your school is letting someone without even a masters teach a college class. Is she a graduate student? Or are they not accredited? Most schools won't even consider you without a masters for a faculty position.

 

[Ashuron]

Personally, let it go..
Do not try to worsen the problem by challenging her with other professor backing you up

 

[bp_psy]

Do the problem again on a piece of paper and include all of the assumptions and reasoning you made and analyze their correctness.Also read the question again and see if you did what the problem really asked you to. When you are finished you should realize were you got the problem wrong(You getting it wrong is the most probable thing) or be completely sure that you got it right.If you still think your solution is valid go to your prof office hour with the paper and explain it to her.I would not go to another prof to complain since I think is bad form.

 

[ZapperZ]

But it is also a matter of learning. The OP needs to know if he/she did it correctly or not, and if the instructor is wrong, she needs to make sure she doesn't penalize other students in the future by perpetuating her error.

Zz.

 

[mathwonk]

I agree to ask another professor. This has happened to me, in that a student asked me about a mistake made by a well qualified very smart full professor. I diplomatically presented it to him, and we fixed it, no problem for the student. Of course I too have made many mistakes, and am always glad to have them pointed out. I even tell students when handing out tests to be sure to check for any errors I may have made and feel free to bring them to me. The only time I have suffered such an injustice myself was when professor declined to review homework graded by his assistant, and the assistant was not very sophisticated. I had no other recourse there. In that case however the student made no error, he was just asking for more detail than I thought the trivial problem called for. Another time I was dinged for just writing down an easy answer I did in my head, when unknown to me the book had answers in the back. The grader accused me, plausibly enough I suppose from his jaded viewpoint, of copying from the back. The fact that I still remember and resent these things almost 50 years later argues to me that you should not let it slide.

 

[Andy Resnick]

Our Physics I midterm exam papers were returned to us this afternoon. One question had been answered wrong by our prof, unfortunately.
<snip>

Should I just let it pass?

If the error is in fact due to the professor (something you need to verify first), then the group of you should approach the Department Chair. The Chair has an interest in making sure faculty are qualified to be teaching the class.

 

[Ashuron]

Just curious, what is the whole question?

 

[micromass]

I would just let it go. I've had enough professors who were wrong and wouldn't admit it. I even had one professor who insisted that x+y=1 described an ellipse, and who didn't believe that there should be squares somewhere...

If the professor is nice and approachable, then you could perhaps talk to her in her office hours. Or maybe you could ask for a second opinion. However, you mentioned that your professor was already annoyed. Then I really would just let it go, you really don't want to have a professor as an "enemy"...

If you do take action (by asking another professor, or talking to the department chair), make sure you take action as a group. If you do such things individually, then bad things might happen...

 

[micromass]

Also, as Ashuron suggested, post the entire question here. Maybe you did make a mistake somewhere. If you let the physicist here take a look at the problem, then maybe we'll find where you went wrong. Or we can confirm that you're 100% correct...

 

[Doc Al]

It was a simple vector question where the gravity is referenced as positive and thus downward acceleration should be positive as well, however she insisted that it is negative because it is going ''down''.

As others have suggested, please post the problem word for word as it was given to you. (Your statement that gravity was referenced as positive, seems a bit odd.)

 

[DR13]

Personally, let it go..
Do not try to worsen the problem by challenging her with other professor backing you up

In life you have to learn to stand up for yourself. If college is supposed to prepare you for the outside world then he should learn to speak up.

I would not go to another prof to complain since I think is bad form.

It's not complaining. If he goes to his professor then his professor will just likely defend the answer on the answer key to avoid looking like a fool (I shouldn't say likely, but it would not be surprising). A separate professor would be able to give an objective viewpoint. Also, in a conceptual problem like this there is sometimes ambiguity in the wording of the problem. Maybe his professor thought he was saying something very clearly but most people interpreted it a different way.

 

[Ryker]

I agree with those saying you should not let it go, but do post the problem here, as well, so that you don't go complain further unnecessarily. Oh, but in any case, if you are going to take this to your professor again or another one to take a look at, do it in a very respectful manner, no matter how angry you might be because of this.

 

[zketrouble]

Well, it's not good to annoy your teachers otherwise they often give you worse grades on your essays; usually unintentionally when their psychology scews with them when they read your name at the top of the paper. So I would be careful when dealing with this, but I agree this issue should be resolved. I would ask your professor to explain why it is wrong, and if you don't believe her, ask another physics professor or the dean of physics. If either verify your claim that her answer to the problem is wrong, politely state your concern with somebody in charge at your school such as a dean.

But I'd be careful with this issue. I remember an anthropology teacher who liked to cite really cliche textbook-style perspectives, and one week he marked my paper down 10% for providing inaccurate information about modern Chinese culture. It didn't matter that I was living in China nor did it matter that I had been living in China/Taiwan on and off since I was seven years old, he simply marked the paper down and denied my claims. So I pushed successfully for him to hand me back that 10% on that paper through the dean, but after that my scores on the essays he assigned went from 85%-95% to 75&-85%; I lost 10% on every essay thereafter. When a teacher doesn't like you they can find a way to manipulate their own grading rubrics to work against you, so it is good to try to stay on good terms if you can. Decide whether or not 10points lost is all that much with respect to the total points you may require throughout the term before deciding if it is worth taking the risk of getting your teacher against you.

 

[micromass]

Well, it's not good to annoy your teachers otherwise they often give you worse grades on your essays; usually unintentionally when their psychology scews with them when they read your name at the top of the paper. So I would be careful when dealing with this, but I agree this issue should be resolved. I would ask your professor to explain why it is wrong, and if you don't believe her, ask another physics professor or the dean of physics. If either verify your claim that her answer to the problem is wrong, politely state your concern with somebody in charge at your school such as a dean.

But I'd be careful with this issue. I remember an anthropology teacher who liked to cite really cliche textbook-style perspectives, and one week he marked my paper down 10% for providing inaccurate information about modern Chinese culture. It didn't matter that I was living in China nor did it matter that I had been living in China/Taiwan on and off since I was seven years old, he simply marked the paper down and denied my claims. So I pushed successfully for him to hand me back that 10% on that paper through the dean, but after that my scores on the essays he assigned went from 85%-95% to 75&-85%; I lost 10% on every essay thereafter. When a teacher doesn't like you they can find a way to manipulate their own grading rubrics to work against you, so it is good to try to stay on good terms if you can. Decide whether or not 10points lost is all that much with respect to the total points you may require throughout the term before deciding if it is worth taking the risk of getting your teacher against you.

I agree 100% with zketrouble. Proceed very carefully! And if possible, try to act as a group instead of individually!

 

[Shackleford]

If you're going to accuse someone of being wrong, you better make damn sure you're right. Post the question and work.

That's a life-lesson applicable to any area.

 

[zketrouble]

micromass: I agree, acting as a group as opposed to individually is much more effective.


And as Shackleford said you better be pretty sure you're right before making accusations, esp. if you want anybody to take you seriously ever again. You started the forum insinuating that your professor isn't all that bright, so if you're wrong this time that doesn't mean you won't be right next time. Be certain of what you are pushing for by asking other physics professors so that you don't burn your bridges; keep them intact for whenever any of your professors misgrade your assignments/exams.

 

[thegreenlaser]

By the title of your thread, I think the first thing you need to do is to stop seeing your teacher as stupid. I would bet that at some point you've stubbornly defended an answer you gave, only to realize later that you were wrong. Does that make you stupid? No, it makes you human. Realize that she's an intelligent person who might have made a mistake, but who also might be right. You'll get a lot further in solving the problem with that sort of attitude.

 

[Ashuron]

OK, new idea..
Do you know anyone who got the answer right?
Since the teacher may not be that stubborn if the whole class answered wrong..

 

[mathwonk]

are you saying you got the whole question wrong because of a disagreement over a minus sign?

 

[flyingpig]

Animals like wolves work in pacts...humans should too

 

[twofish-quant]

In life you have to learn to stand up for yourself. If college is supposed to prepare you for the outside world then he should learn to speak up.

In life you have to learn when it's not worth the trouble. If college is supposed to prepare you for the outside world, then sometimes you have to learn to let things go. A lot of getting through life is to know which fights are worth it and which ones aren't.

 

[symbolipoint]

The course in which this troubling exercise occurs is Physics 1, and you say,

It was a simple vector question where the gravity is referenced as positive and thus downward acceleration should be positive as well, however she insisted that it is negative because it is going ''down''.

The class is in a learning situation in which students are developing critical thinking and learning conventions of problem descriptions and problem solving. Many students will be annoyed.

More than that, the B.S. degree in Engineering may not be everything about this instructor. What else was not stated but in fact included in her courses and experience? The mere degree title of Bachelor of Science does not always tell everything.

 

[Bradwast88]

Could you please post the problem and both your answer and her answer?

 

[Headacheguy]

I'm sorry for the title, I made the evaluation based on her lectures and the way she constructs/answers our quizzes.

I've had several conflicts with her before. Once was when she considered the correct significant figures wrong and that all of our answer should be in two/three decimal places. Another time was when she said that the equilibrant and the resultant vector are the same (both in direction and magnitude). In our first quiz she marked 25% of my answers wrong because I used the cartesian plane (I find it easier using the cartesian plane for my vectors) than a polygon vector diagram; the diagrams are essentially the same. I should have got 98% on that quiz if my diagram were checked, I let it slip than argue that time. But this time is worse. Midterm exam is a large chunk of our grade.

She also isn't good at teaching, she comes to class and reads the lecture from the textbook. Our class is supposed to be 6 hrs a week, meeting twice, 3 hours lecture, and 3 hrs lab. She only spends 2 hrs each meeting, she says she needs to catch the train.

I am sorry for my ranting. Really frustrated. I think it's just unfair that I get to spend my time studying the material in advance, before even classes had started, and then she just comes in class unprepared, not doing her part of the work.

Here's the question:

A 2 kg body is supported by a massless string. The body is accelerating downwards at a rate of 4.9 m/s^2. Calculate the tension on the string.

(It was pretty odd that this question is in the midterm exam and is worth 10 points.)

What I did was:
From F = ma:
T + (-mg) = -ma (Took the tension T as positive, therefore the weight -mg, is negative since the force is exerted on the opposite direction. The resultant force of this body is downwards, same direction with the weight, as stated in the question, -ma.)

T = mg - ma
T = 2 kg ( 9.8 m/s^2 - 4.9 m/s^2)
T = 9.8 N
T = 10 NHer solution was a bit different because she chose the direction of the motion of the body as the positive direction. Either way, the answer should have been the same. Hence, the weight is positive, so is the direction of the resultant force, and the tension negative because it is on the upwards direction.

mg - T = ma
T = mg - ma
T = m (g - a) (This was where it went wrong, I think)
T = 2 kg [ 9.8 m/s^2 - (-4.9 m/s^2)] (The acceleration was negative because it was going "down", she explained)
T = 29.4 N (Again her answer was not in the correct significant figures.) Most of my classmates had the same answer as mine.

Please forgive me if my solution is wrong.

 

[Phrak]

"It was a simple vector question where the gravity is referenced as positive and thus downward acceleration should be positive as well, however she insisted that it is negative because it is going ''down''."

"Referenced as positive" has no meaning. Positive what and in what coordinate system?

 

[Doc Al]

A 2 kg body is supported by a massless string. The body is accelerating downwards at a rate of 4.9 m/s^2. Calculate the tension on the string.

Nothing ambiguous about the question.

What I did was:
From F = ma:
T + (-mg) = -ma (Took the tension T as positive, therefore the weight -mg, is negative since the force is exerted on the opposite direction. The resultant force of this body is downwards, same direction with the weight, as stated in the question, -ma.)

T = mg - ma
T = 2 kg ( 9.8 m/s^2 - 4.9 m/s^2)
T = 9.8 N
T = 10 N

Perfectly correct.

Her solution was a bit different because she chose the direction of the motion of the body as the positive direction. Either way, the answer should have been the same.

mg - T = ma
T = mg - ma
T = m (g - a) (This was where it went wrong, I think)
T = 2 kg [ 9.8 m/s^2 - (-4.9 m/s^2)] (The acceleration was negative because it was going "down", she explained)
T = 29.4 N (Again her answer was not in the correct significant figures.)

Comically wrong. (Ask her how the tension would change if the acceleration were upward. Then ask her what the tension would be if the body were accelerating at 9.8 m/s^2 downward.)

I would indeed approach another professor. With discretion.

 

[cristo]

It sounds like the issue is more than just this one problem, in which case you should really go and talk to someone else in your department and express your concerns for the class.

As for the problem, your answer is correct (although I'd probably keep it as 9.8N).

 

[Headacheguy]

After I argue with the professor, I went stupid and decided to not pretend to listen anymore, (I usually study at home with MIT CW, because most of the time I can't understand her) read a novel from my phone.

She caught me and asked me to go out and not attend her lectures anymore, and to just see her on the final exam. She's mad at me, that's for sure.

Sidenote: Only 7 out of 51 passed the exam. Most of classmates can't/doesn't want to self-study.

 

[Headacheguy]

@Cristo: I answered 10 N because of the 2 kg measurement, only one significant figure.

Edit: @Phrak: I'm sorry if I was ambiguous with my terms. What I meant was that, our professor chose the downward direction as positive, hence it follows that the weight (sorry for using gravity) is positive.

@Doc_Al: It is impossible to argue with her, I doubt she has a clear understanding of the topic. Before (on the equilibrant, resultant issue), when I tried to argue from what I have read from my book about the definition of the term, she remarked that she doesn't care what I had read on my textbook.

 

[Doc Al]

@Cristo: I answered 10 N because of the 2 kg measurement, only one significant figure.

Technically, you are correct. But I would not distract the issue away from the egregious physics error on her part by bringing up significant figures.

 

[Headacheguy]

Oh, right. Thanks, Doc Al. :)

Thanks everyone. I'm still undecided whether or not I would bring this up with another professor. I'm afraid she would get pretty mad at us. One thing I've realized is that sometimes you have to decide whether the ''right thing'', (technically) is the right thing to do (politics of academia; must obey authority).

Regards to the professor background issue: I've never had a professor with a Ph. D. I've never heard of a professor with a research Ph.D that teaches in the university, I know of two professors who has Ph.D. in education. The university has a student population of 50,000 undergrads.

 

[cristo]

It's ultimately up to you, but a teacher who refuses to accept that she's incorrect, even after having the problem explained to her, needs to be called out.