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You are not logged in. #1 20130710 03:22:25
spacial geometryA rectangle with height 8 and length 24 is wrapped around a cylinder with height 8. The rectangle perfectly covers the curved surface of the cylinder without overlapping itself at all. What is the volume of the cylinder? I see you have graph paper. You must be plotting something #2 20130710 03:43:46
Re: spacial geometry
I'll give you a brief outline of a workable method for each of these. After you've given them a try, post back with answers for checking or ask for more help. You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #3 20130710 03:59:44
Re: spacial geometryi am stuck on visualiztion for (ii) and i think (i) is 1152/pi I see you have graph paper. You must be plotting something #4 20130710 04:04:37
Re: spacial geometryalso, is (iii) 36pi? the radius is 3. I see you have graph paper. You must be plotting something #5 20130710 17:08:37
Re: spacial geometryhi cooljackiec, You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #6 20130711 04:51:42
Re: spacial geometryyea my dad said it was easier viewing it in 2D with the plane as a line. then the pythag made radii 7. then it was easy I see you have graph paper. You must be plotting something #8 20130711 07:59:50
Re: spacial geometrymy radius of the sphere was 7. what is the little r?? I see you have graph paper. You must be plotting something #9 20130711 08:52:49
Re: spacial geometry7 is correct for the sphere radius. The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #10 20130711 17:14:04
Re: spacial geometryWhoops, my mistake. I was working with circumference = 24 pi. That leads to r = 12 and a 'nice' Pythagorean triple so I didn't think I had made an error. With area = 24 pi I also get R=7. You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #11 20130712 02:48:35
Re: spacial geometryhmm, it seems i got the answer by subtracting the volume of the prism from the 4 pyramid shaped things. Thanks anyways! Last edited by cooljackiec (20130712 03:02:27) I see you have graph paper. You must be plotting something 