两根梁的尺寸、受力和支承情况完全相同，但材料不同，弹性模量分

搜题请搜索小程序“爱下问搜题”

问题单项选择题

两根梁的尺寸、受力和支承情况完全相同，但材料不同，弹性模量分别为E₁和E₂，且E₁=7E₂，则两根梁的挠度之比为（）。

A.y₁/y₂=1/√7

B.y₁/y₂=1/7

C.y₁/y₂=1/8

D.y₁/y₂=1/√8

答案

参考答案：B

改错题

Behind my apartment, there is used to be a dirty and 1.___________

messy comer. Bits of plastic bags hanged on the trees. 2.___________

Broken bottles were left laying here and there. There was 3.___________

a damaging car in the center. The whole comer gave off an 4.___________

unpleasant smell. One year ago, we decided to turn it in a 5.___________

beautiful park. Since then, great changes have been taken place 6.___________

in that comer. All the rubbish have been cleared away. Flowers 7.___________

and young trees have planted all over. Now birds come 8.___________

here to sing, children come here to play, and adults come here 9.___________

to enjoy our peaceful life. It has taken on a new look. 10.___________

填空题

差速器的作用是能使同一驱动桥的左右车轮以不同速度旋转并（）。