Date: Mon, 19 May 2008 13:52:09 +1000 From: Greg 'groggy' Lehey <grog@FreeBSD.org> To: Jim Capozzoli <saltmiser@gmail.com> Cc: freebsd-chat@freebsd.org Subject: Re: slide rules Message-ID: <20080519035209.GT46655@dereel.lemis.com> In-Reply-To: <37f72b1f0805181418j16efd60fge243160dbfdc6789@mail.gmail.com> References: <37f72b1f0805181418j16efd60fge243160dbfdc6789@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
--KxKI/R+N9hudrWbn Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Sunday, 18 May 2008 at 17:18:30 -0400, Jim Capozzoli wrote: > So, I pulled out the slide rule yesterday that's older then I am..and > I figured out how to multiply/divide on it. Is there anybody out > there still using slide rules for day to day math? Or does anybody > have any interesting stories/reminiscences about slide rules? I was > considering figuring out how to do Trig on it and then taking my Trig > final with it. :) Heh. I don't know where my slide rule is, but it's definitely a lot younger than I am. So the following is from memory. It applies to the conventional slide rules that I know, with C/D scales going from 1 to 10 at the bottom, and A/B scales going from 1 to 100 at the top (giving squares of the corresponding scale below). To multiply two numbers, you place the 1 on the C scale (bottom of the slide) against the first number on the D scale (directly below on the body). Move the cursor (or your eye :-) to the second number on the C scale, and read off the result on the D scale. To divide one number by another, you place the divisor the C scale above the dividend on the D scale. Read off the quotient on the D scale below the 1 on the C scale. Greg -- See complete headers for address and phone numbers. --KxKI/R+N9hudrWbn Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4 (FreeBSD) iD8DBQFIMPlpIubykFB6QiMRAvOIAKCrWfDNQFG5dk1nN2JauI5Mkk2D8ACgh3b/ AdJVQn2L60Kp3jEd1m5lwv4= =LhMi -----END PGP SIGNATURE----- --KxKI/R+N9hudrWbn--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20080519035209.GT46655>