题目内容
已知母线长为1的圆锥的侧面展开图的圆心角为![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_ST/0.png)
【答案】分析:求出圆锥的侧面展开图扇形的弧长,再求底面半径,求出圆锥的高,即可求它的体积.
解答:解:圆锥的侧面展开图扇形的弧长,即底面圆的周长为
π•1=
π,于是设底面圆的半径为r,
则有2πr=
π,所以r=
,
于是圆锥的高为h=
=
=
,
该圆锥的体积为:
=
π.
故答案为:
π.
点评:本题考查圆锥的体积,考查计算能力,是基础题.
解答:解:圆锥的侧面展开图扇形的弧长,即底面圆的周长为
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_DA/0.png)
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_DA/1.png)
则有2πr=
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_DA/2.png)
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_DA/3.png)
于是圆锥的高为h=
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_DA/4.png)
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_DA/5.png)
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_DA/6.png)
该圆锥的体积为:
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_DA/7.png)
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_DA/8.png)
故答案为:
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131023213209173937978/SYS201310232132091739379016_DA/9.png)
点评:本题考查圆锥的体积,考查计算能力,是基础题.
![](http://thumb.zyjl.cn/images/loading.gif)
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