棱柱交叉科

播放段落

In This Lesson
::在本课程中

播放段落

Y ou will  investigate  3-dimension al shapes . Recall that a  3- dimensional shape with polygon sides  is a polyhedron . Prisms and pyramids are examples of . All the sides of a polyhedron lie  on different planes (a plane is a 2- dimensional surface that extends infinitely in all directions) and intersect to form faces , edges and vertices . S pheres  and cylinders are not considered polyhedrons because they have curved sides.
::您将调查三维形状。 请注意, 多边多边形的三维形状是一个多面形。 棱柱和金字塔就是例子 。 多面形的两侧都位于不同的平面上( 平面是两维表面, 无限延伸于所有方向) , 交叉形成面、 边缘和脊椎。 球体和圆柱体不被视为多面形, 因为它们的侧面已经弯曲 。

播放段落

The polyhedron above is a right  square prism . The prism is "right" because all of the faces are perpendicular or parallel to each other.  The two  faces of the prism that are squares are called the bases , because they are parallel and the only two square faces. The other four faces are called lateral faces and are all .  A right triangular prism would have two triangles as the bases instead of squares, but the lateral faces would still be rectangles.
::上面的一面形是右方形。 棱镜是“ 右方形 ” , 因为所有面孔都是垂直的或平行的。 方形的两面面面被称为基座, 因为它们是平行的, 只有两个平面。 其它四面面面面被称为横向面, 它们都是正方形 。 右三角棱镜将有两个三角形作为基座而不是正方形, 但横向面仍然是矩形 。

播放段落

In this lesson, you are going to be studying cross sections of prisms . A cross section is  an intersection of a plane with a three-dimensional figure. They can also be referred to as a "slice" or "plane section." 
::在此课中, 您将研究棱晶的交叉部分。 交叉部分是平面与三维图的交叉部分。 它们也可以被称为“ 切片 ” 或“ 平面 ” 。

 

---

播放段落

Prism  Slicing
::棱晶切片

播放段落

How many different ways could you intersect a plane with a rectangular prism ? Use this interactive to view the prism and slice it with the plane. Try to  create the following cross sections: a rectangle , square, triangle , , pentagon (5 sided 2D figure), and hexagon (6 sided 2D figure).
::您可以用多少种不同的方式将平面与矩形棱柱相交叉? 使用此交互式方式查看棱柱, 并用平面将其切除。 尝试创建以下交叉区域: 矩形、 方形、 三角形、 边形、 五边形( 5 面 2D 图) 和 六边形( 6 面 2D 图) 。

 

 

 

 

播放段落

Discussion Question
::讨论问题

播放段落

Would it be just as easy to answer these questions without the interactive? What physical tools could you use? What advantages do 3D computer models provide?
::如果没有互动,回答这些问题是否同样容易?你能使用哪些物理工具?3D计算机模型有什么好处?

---

播放段落

Prism Slicing , Part 2
::棱晶切片,第2部分

播放段落

How many different ways could you intersect a plane with a triangular  prism? Use this interactive to view the prism and slice it with the plane. Try to create the following cross sections: a rectangle, square, triangle, parallelogram, pentagon (5 sided 2D figure), and hexagon (6 sided 2D figure).
::您可以用多少种不同的方式将平面与三角棱镜相交叉? 使用此交互式方式查看棱镜, 并用平面切开它。 尝试创建以下交叉区域: 矩形、 方形、 三角形、 平行图、 五边形( 5 面 2D 图) 和 六边形( 6 面 2D 图) 。

 

 

 

 

播放段落

You now  know the  different types of cross sections a prism can have.  Next, you will explore  the cross sections of a cylinder . A cylinder is  similar to a prism, but with circles as bases. Therefore, there is only one lateral face that unfolds to a rectangle (like when you unwrap the label of a soup can).
::您现在知道棱柱可以有不同类型的交叉区块。 接下来, 您将探索圆柱体的交叉区块。 一个圆柱体与棱柱相似, 但圆圈是底部。 因此, 只有一张横向面孔可以显示为矩形( 比如您解开汤汤罐标签时) 。

 

---

播放段落

Cylinder  Slicing
::气瓶切碎

播放段落

What are the different types of cross sections that a cylinder can produce?  Use this interactive to view the cylinder  and slice it with the plane. Try to form a rectangle,   circle , and oval cross section.
::圆柱体可以产生哪些不同类型的交叉部分? 使用此互动方式查看圆柱体, 并用平面切分。 尝试形成矩形、 圆形和 oval 交叉部分 。