请输入您要查询的字词:

 

单词 IntegrationWithRespectToSurfaceAreaOnAHelicoid
释义

integration with respect to surface area on a helicoid


To illustrate the result derived in http://planetmath.org/node/6666example 3, let us compute the area of a portion of helicoid of height h and radius r. (This calculation will tell us how much material is needed to make an .) The integral we need to compute in this case is

A=d2A=0h/c0rc2+u2𝑑u𝑑v=
0h/c(12rc2+r2+c22log{rc+1+(rc)2})𝑑v=
rh21+(rc)2+ch2log{rc+1+(rc)2}

As a second illustration, let us compute the second moment of a helicoid about the axis of rotation. In mechanics, this would be called the moment of inertia of the helicoid and determines how much energy is needed to make the screw rotate. This is determined as follows:

(x2+y2)d2A=0h/c0ru2c2+u2𝑑u𝑑v=
0h/c(r(2r2+c2)8c2+r2-c48log{rc+1+(rc)2})𝑑v=
rh(2r2+c2)81+(rc)2-hc38log{rc+1+(rc)2}

http://planetmath.org/node/6660main entryhttp://planetmath.org/node/6666previous examplehttp://planetmath.org/node/6668next example

随便看

 

数学辞典收录了18232条数学词条,基本涵盖了常用数学知识及数学英语单词词组的翻译及用法,是数学学习的有利工具。

 

Copyright © 2000-2023 Newdu.com.com All Rights Reserved
更新时间:2025/5/4 16:02:09