还有一道GWD2-6

dd笑颜

20 ft

 

 

 

 

 

 

 

 

 

The figure above shows the dimensions of a semicircular cross section of a one-way tunnel.  The single traffic lane is 12 feet wide and is equidistant from the sides of the tunnel.  If vehicles must clear the top of the tunnel by at least ½ foot when they are inside the traffic lane, what should be the limit on the height of vehicles that are allowed to use the tunnel?

 

A.     5½ ft

B.     7½ ft

C.     8 ½ ft

D.     9½ ft

E.      10 ft

图上画的是个半园，直径为20FT。题目没怎么看懂，选了D，正确答案是B，请大牛解释，谢谢！

qiuhailing01

我的数学不好,帮你解答当作练习:

题目:上图为一单向隧道载面尺寸.遂道直径为20.一长车(通常指我们平时见到的货柜车)宽12,与(遂道两侧)距离相等.如该长车进入遂道,其上方需减少至少1/2的高度,问此车进遂道的限高.

即(10的平方-6的平方)开根再减去1/2.

B.

雪舞纷飞

半径是斜边，6是直角边，高就是8，但是要离开1/2，所以再减去

jillchenyy

看不到图，我没理解为什么半经是斜边，能再解释一下吗？谢啦

zihuanzihuan

谢谢