I know different sites have different rules for this, I'm only asking now because this is the first "homework" question I've come across.
Should we allow these types of questions? If so, under what – if any – conditions?
I like the fact the OP explicitly stated it was a homework question.
Too many times I've suspected a question of being homework based and it annoys me how it's posted a "real life" problem when it really isn't.
I'm perhaps biased because my worst experience was in an on-line chatroom where some girl was asking me questions about MS-DOS which I unwittingly answered only to be told 1/2 hour later "Thanks I was writing an exam and you helped me with the answers". I felt so abused....
College has sure changed since I attended (Northeastern University) in the late 1960's.
"Back in the day", electronic calculators, which were insanely expensive, were verbotten in class. We worked out calculations on a sliderule or longhand on paper. The Professors wanted us to understand how to do the math, not just punch in some numbers into a machine and look at the answer that was given to us. As a result, we went off to be much better Engineers.
If students want to use this forum as a sort of CliffsNotes on steroids, more power to them. Far be it from me to snub my nose at shortcuts. However, using this site to research for information is a lot different than having someone else (us) do their homework for them. While I do enjoy the intellectual exercise of helping someone figure out an answer to their issue, it's not like I have unlimited time to do other people's work.
I generally do not look at homework related questions. They seem to usually be written by extremely lazy people who haven't even tried to figure out the problem on their own. Furthermore, like many assignments in academia, the problems these students are sent off to research typically bear little resemblance to anything a real Engineer might be faced with in the field.
I don't know that I'd go so far as to make a blanket policy that all homework questions should be declared off-topic. But they should certainly be liberally downvoted if the question and potential answers add little or no value to the site's knowledge base.