Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

This question came up on a pub quiz last night. The answer was parabola.

I disagreed, because I thought I remembered that angles could go off into infinity too. An angle is two rays whose endpoints are shared, so would that also count as a "bend" ? Or is there another name for this type of angle?

share|cite|improve this question
There isn't enough information to answer the question. There are infinitely many types of shapes that look like this, e.g. a catenary: – Qiaochu Yuan Feb 2 '11 at 16:35
I guess my point is is that based on the question it can not just be a parabola as the Quizmaster indicated! – GJTorikian Feb 2 '11 at 16:40
To add to Qiaochu's comment, even a hyperbola is a better answer for two reasons: (a) among conic sections, there are more hyperbolas than parabolas (in the sense that a parabola can be taken as a degenerate limit of a family of hyperbolas) (b) related to the first part is the consideration of the orbit of an object flying in from far away (infinity), approaching the solar system, and flying away again. For such an object it is generally more likely the orbit is hyperbolic than parabolic. – Willie Wong Feb 2 '11 at 16:44
up vote 3 down vote accepted

This is the second worst pub quiz question that I have come across. There are so many "curves with single bends that go to infinity" that the question is meaningless.

BTW, the worst question was this: "Which continent is wider in the South than in the North?" You might like to ponder that for a microsecond.

The official answer from the book was, if you can believe it, Antarctica. I was flabbergasted (and said so). Some years later, I stumbled upon the key to this idiocy, quite by accident, while browsing my Encyclopaedia Britannica (as you do). An article on the continents said, quite reasonably (I am paraphrasing here): "With the exception of Antarctica, all continents are wider in the North than in the South." The question setter obviously read this exact same sentence and thought that a question could be forged out of it.

share|cite|improve this answer
That quiz question you mention is indeed abysmal. – Raskolnikov Feb 2 '11 at 17:20
I've heard horror stories of pub quiz questions asking for the value of pi, with the "correct" answer being 22/7. Also, Australia is surely wider at the south than the north, no? Not that the question is well defined. – Oscar Cunningham Feb 2 '11 at 19:05
Good to know that there are lousy pub quizmasters the world over! :) – GJTorikian Feb 3 '11 at 1:33

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.