go to jove.com

HIGH SCHOOL

Mathematics

Concept Videos

Calculus

This is a free preview. For full access

Vectors in Space

Modeling Cylindrical Surfaces in 3D

Description

Cylindrical surfaces in three-dimensional space come from moving a two-dimensional curve in a straight line. As the curve slides, it leaves behind translated copies that build a surface. These copies form parallel rulings, which are straight lines in the same fixed direction.

This idea helps desc...

Transcript

在三维空间中,当一条二维曲线沿一条直线延伸时,会形成一个柱面。该曲线称为轮廓曲线,代表形状的横截面。此过程会生成由平行线组成的曲面,这些平行线称为直母线,沿固定方向延伸。

在直角坐标系中,当一个方程不包含三个变量中的某一个时,通常可以确定其为柱面。例如,在 y = x2 中,变量 z 未出现。

该方程在 xy-平面内形成一条抛物线,而方程中缺少 z 表明该曲线沿 z-轴无限延伸。由此形成的曲面称为抛物柱面。

类似的概念也适用于圆形轮廓曲线。例如,一个圆在 xy-平面可沿 z-轴形成一个圆柱体,类似于一根在各个高度上具有...