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 Subject: math conversion Category: Science > Math Asked by: steveair-ga List Price: \$5.00 Posted: 16 Dec 2003 06:50 PST Expires: 15 Jan 2004 06:50 PST Question ID: 287679
 ```I suppose that this is really two questions, but I'm presenting them as one; What is the weight, in U.S. lbs., of a one inch length of 3/4 inch diameter rod of lead (11.35 gm/cc)? What is the weight, in U.S lbs., of a one inch length of 3/4 inch diameter rod of tungsten (19.3 gm/cc) ?```
 Subject: Re: math conversion Answered By: endo-ga on 16 Dec 2003 07:34 PST
 ```Hi, Thank you for your question. The following are conversions of the units we will use: 1 inch = 2.54 cm 3/4 inch = 1.905 cm 1 lbs = 453.5924 g 1-) For the first rod we have: Volume of the rod = 1.905 x pi x 2.54 = 15.201 cc diameter length Weight of the rod = 15.201 x 11.35 = 172.53 g volume density Weight of the rod in lbs = 172.53/453.59 = 0.38 lbs 2-) For the second rod we have: Volume of the rod = 15.201 cc Weight of the rod = 15.201 x 19.3 = 292.38 g Weight of the rod in lbs = 292.38/453.59 = 0.65 lbs I hope this answers your question. If anything is unclear or you require any clarifications, please do not hesitate to ask. Thanks. endo Search strategy weight converter ://www.google.com/search?hl=en&lr=&ie=ISO-8859-1&safe=off&q=weight+converter Interactive Units Converter http://www.convert-me.com/en/convert/weight``` Clarification of Answer by endo-ga on 16 Dec 2003 10:38 PST ```Ooops, thanks for that, sorry I made a very silly mistake. Racecar is right. The volume of the rods are: 0.9525^2 x pi x 2.54 = 7.24 cc r^2 x pi x length Weight of rod 1: 7.24 x 11.35 = 82.17 g Weight of rod 1 in lbs: 82.17 / 453.59 = 0.18 lbs Weight of rod 2: 7.24 x 19.3 = 139.72 g Weight of rod 2 in lbs: 139.72 / 453.59 = 0.31 lbs Sorry again for the confusion. Thanks to Racecar for pointing out the mistake. Regards, endo```
 Subject: Re: math conversion From: racecar-ga on 16 Dec 2003 10:28 PST
 ```This answer needs some fixin', endo-ga. As I know you know, the area of a cylinder is not pi*diameter*length. The correct volume is 7.240 cubic centimeters.```
 Subject: Re: math conversion From: racecar-ga on 16 Dec 2003 10:34 PST
 ```Ooops, for 'area of a cylinder', read 'volume of a cylinder'... 'long as I'm adding a second comment, the correct weights are .181 and .308 lb.```
 Subject: Re: math conversion From: steveair-ga on 16 Dec 2003 18:38 PST
 ```Thanks, Steve```
 Subject: Re: math conversion From: kik-ga on 17 Dec 2003 04:14 PST
 `Ain;t weight = mass * gravity ?`
 Subject: Re: math conversion From: vince6567-ga on 06 Jan 2004 14:02 PST
 ```A good website for conversion of various units is: http://www.onlineconversion.com/ It converts most anything to anything.```