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        riddles >> what happened >> Finally: an interesting math class
        
(Message started by: Iceman on Dec 18^th, 2007, 5:10am)

Title: Finally: an interesting math class
Post by Iceman on Dec 18^th, 2007, 5:10am

Your math professor is holding a class, and all the students are currently using compasses, drawing circles. Suddenly, the professor proposes the riddle below, & the one who solves it 1st wouldn't have to take the test tomorrow, for he/she will get an A for it right away.

What is the quickest way for you to make several circles of different sizes, by using one object alone with your hands, but w/o using objects more advanced than your compass?

Edit: I've replaced calipers with compasses.

Title: Re: Finally: an interesting math class
Post by Whiskey Tango Foxtrot on Dec 18^th, 2007, 11:25am

[hide]~~Put a pin in the table and tie a string to it. Tie pencils at your desired radii.~~[/hide]

[hide]Use the pre-punched holes in your ruler and fix one end with another pencil.[/hide]

Title: Re: Finally: an interesting math class
Post by Iceman on Dec 18^th, 2007, 12:25pm

on 12/18/07 at 11:25:27, Whiskey Tango Foxtrot wrote:

[hide]Use the pre-punched holes in your ruler and fix one end with another pencil.[/hide]

Not bad, but it looks like more objects than one to me. ;)

Title: Re: Finally: an interesting math class
Post by tiber13 on Dec 18^th, 2007, 1:41pm

First, wats a caliper?
is it like a compass?

[hide]Anyways, if your already drawing circles with calipers, just use the calipers[/hide]

Title: Re: Finally: an interesting math class
Post by Iceman on Dec 18^th, 2007, 2:05pm

on 12/18/07 at 13:41:00, tiber13 wrote:

First, wats a caliper?
is it like a compass?

It is that basic thing you use in school to draw circles. I don't know some other name of it, but caliper looks correct to me. Am I wrong? Maybe compass is the right one, if it has two meanings. And here is a picture of it below. I think it is the correct picture, but it looks rather small, so I cannot see clearly all of its parts, but it looks fine to me. Don't you use caliper back at school?

on 12/18/07 at 13:41:00, tiber13 wrote:

[hide]Anyways, if your already drawing circles with calipers, just use the calipers[/hide]

There it is again: plural. I said just one thing that you could use with your hands only. ;)

Title: Re: Finally: an interesting math class
Post by towr on Dec 18^th, 2007, 2:42pm

A caliper (http://en.wikipedia.org/wiki/Caliper) is for measuring sizes; your picture is one for measuring the inside of things.
A compass (http://en.wikipedia.org/wiki/Compass_%28drafting%29) can be used to actually draw circles, since one end has a point and the other a drawing implement (typically a piece of pencil-lead, but there are versions where you can insert a pen or other things. A knife is useful if you want to cut out circles, rather than draw them.)

I don't see why it should be a problem to use the latter to draw circles of different sizes.

Title: Re: Finally: an interesting math class
Post by denis on Dec 18^th, 2007, 3:10pm

Take a sheet of paper and roll into a cylinder shape.
Stand one end of cylinder shape paper on another sheet of paper that is flat on the table. Trace a circle on the flat piece of paper using as a guide the outside edge of the cylinder that intersects the flat piece of paper.

You can repeat the process and use different size cylinders using the same sheet of paper.

Title: Re: Finally: an interesting math class
Post by JiNbOtAk on Dec 18^th, 2007, 5:13pm

on 12/18/07 at 05:10:53, Iceman wrote:

What is the quickest way for you to make several circles of different sizes, by using one object alone with your hands, but w/o using objects more advanced than your caliper?

When you say one object alone, is that including or excluding the pen/pencil that you use to draw ?

I've actually seen a marker ( a person who measures and mark the steel plates for steel fabrication ) construct a circle using just his chalk and measuring tape. Though I'm not sure how precise it is, it looked better than my attempt with a pencil and a compass. :P

Title: Re: Finally: an interesting math class
Post by Iceman on Dec 19^th, 2007, 3:05am

Nah. We need speed here, not lag.

on 12/18/07 at 14:42:54, towr wrote:

Live and learn. Thanks for the input. I modified the riddle accordingly too. And I suppose the technical name would be compass with interchangeable attachments.

Title: Re: Finally: an interesting math class
Post by mikedagr8 on Dec 19^th, 2007, 3:18am

Cut yourself enough so that you can bleed to create cirlces by moving the wound up and down, or spit onto the paper, then circle the spit accordingly.

Title: Re: Finally: an interesting math class
Post by Iceman on Dec 19^th, 2007, 3:24am

Soooooooooooooooooooooooooooo slow. :P

Title: Re: Finally: an interesting math class
Post by mikedagr8 on Dec 19^th, 2007, 3:41am

on 12/19/07 at 03:24:54, Iceman wrote:

Soooooooooooooooooooooooooooo slow. :P

By the time it took you to write that, I could have drawn multiple circles of different sizs by using the second method. 8)

Title: Re: Finally: an interesting math class
Post by Whiskey Tango Foxtrot on Dec 19^th, 2007, 8:48am

Take your shirt off and form it into a circle.

Title: Re: Finally: an interesting math class
Post by Iceman on Dec 20^th, 2007, 12:50am

on 12/19/07 at 03:41:18, mikedagr8 wrote:

By the time it took you to write that, I could have drawn multiple circles of different sizs by using the second method. 8)

All right. How many seconds do you need then, approximately? Btw, I have no idea what you're talking about.

on 12/19/07 at 08:48:51, Whiskey Tango Foxtrot wrote:

Take your shirt off and form it into a circle.

Huh? You have to make circles from scratch.

Title: Re: Finally: an interesting math class
Post by mikedagr8 on Dec 20^th, 2007, 3:22am

on 12/20/07 at 00:50:14, Iceman wrote:

All right. How many seconds do you need then, approximately? Btw, I have no idea what you're talking about.

I can draw 5 circles of various sizes in 16 seconds. I can probably draw faster, but I'm not the kind of person who has control over these fine movements.

Title: Re: Finally: an interesting math class
Post by Iceman on Dec 20^th, 2007, 6:13am

on 12/20/07 at 03:22:05, mikedagr8 wrote:

I can draw 5 circles of various sizes in 16 seconds.

You can do better than that. ;)

Title: Re: Finally: an interesting math class
Post by Grimbal on Dec 20^th, 2007, 6:48am

[hide]Throw a stone in the pond.[/hide]

But it hardly deserves an A in maths.

edit: typo

Title: Re: Finally: an interesting math class
Post by Iceman on Dec 22^nd, 2007, 4:28am

on 12/20/07 at 06:48:48, Grimbal wrote:

But it hardly deserves an A in maths.

The teacher is a bit exhibitionist and he has a big heart, what? And only one student got A like that. Chinese say: 'may I live in interesting times,' and to me the above class was interesting. ;) And I didn't lose my alien tricks, not all of them anyway. 8)

Title: Re: Finally: an interesting math class
Post by Iceman on Dec 22^nd, 2007, 3:39pm

on 12/20/07 at 06:48:48, Grimbal wrote:

[hide]Throw a stone in the pond.[/hide]

You got it Grimbal.

Title: Re: Finally: an interesting math class
Post by Iceman on Dec 24^th, 2007, 5:37am

Btw, how would you rate this riddle? To me it looks nice; Nothing special, but nice.

The reason I'm asking this is because of a few riddlers here. I won't mention their names, yet, but they suggested that my recent riddles lost my magic touch >:( from before. I want the truth and nothing but the truth. I'm not kidding. ::)

Title: Re: Finally: an interesting math class
Post by JiNbOtAk on Dec 25^th, 2007, 9:12pm

You want the truth Icey ? You're right, you haven't lost the magic touch. After all, one cannot lose what one doesn't have, right ? ::)

Title: Re: Finally: an interesting math class
Post by Iceman on Dec 26^th, 2007, 3:06am

You think that you can break my heart and turn me into stone? You think that I'm nymph Echo since on this forum I have my voice only? So thanks for the heavy critique, for it might only help me to improve my riddles. 8) :P

Title: Re: Finally: an interesting math class
Post by shasta on Jan 18^th, 2008, 6:54am

on 12/24/07 at 05:37:23, Iceman wrote:

Btw, how would you rate this riddle? To me it looks nice; Nothing special, but nice.

I like it. I think this one's worthy of polishing up. Perhaps you might tell it as a story?

"Today's math class was actually interesting! For starters, because it was such a nice day out and there was no wind to blow our papers around our teacher decided to hold class outside! We sat on the benches by the pond, and the teacher set up a portable chalkboard and podium from which he gave us today's geometry lesson. We were having trouble paying attention because a pair of squirrels kept chasing each other around the benches. Just as the teacher was telling us how we needed to learn to ignore the squirrels they ran up one side of his leg and down the other! Finally he gave up and decided to have the students engage in a circle-making race, saying whoever made the most circles of different sizes in the next 10 seconds would get an automatic A on Friday's test! We all drew as fast and furiously as we could, but the student who won was none other than Slowpoke John, the slowest moving kid in the whole state! And he did it at his usual speed! Can you guess how?"

Title: Re: Finally: an interesting math class
Post by Iceman on Jan 18^th, 2008, 8:41am

........and I thought that I'm the one with great imagination.

Btw, someone suggested to throw the compass in the lake, not pebble. But I wonder would that make a perfect circle? It probably would, but I'm not that good at math. :-[

Title: Re: Finally: an interesting math class
Post by thecow135 on Jan 18^th, 2008, 5:34pm

define perfect circle. i dont think there are any perfect circles that can be drawn in nature, or anywhere else for that matter. the perfect circle is a myth, a perception.