题干

如图所示,质量分别为m1、m2的A、B两小球分别连在弹簧两端,B端用细线固定在倾角为30°光滑斜面上,若不计弹簧质量,在线被剪断瞬间,A、B两球的加速度分别为(  )

A:aA=0

B:aA= g2

C:aB= g2

D:aB= (m1+m2)g2m2

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答案(点此获取答案解析)

A,D

同类题1

假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下作文。作文中共有10处语言错误,每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。

增加:在缺词处加一个漏子符号(∧)并在其下面写出该加的词。

删除:在错的词下划一横线,并在该词下面写出修改后的词。

注意:1  每处错误及其修改均仅限一词;

2只允许修改10处,多者(从第11处起)不计分。

Dear Jack,

    How is everything going recently? I'm writing to tell you something more about my birthday. The other day we hold aparty to celebrate my 18th birthday. I received many presents from my friends and parents, including cards, books, CDs or so on. During the party we sang and danced, having good time. I thanked my friends for his help and company. At the meantime, I showed my sincere appreciation to my parents for bringing me up. Now I grow up, that means I should shoulder more responsibilities. I'll try my best to share more houseworks to reduce their burden. It's high time that I dosomething to repay them.

    How did you celebrate your 18th birthday? I'm looking forward to hear from you soon.

                                                                                                                                                                                 Yours Sincerely

                                                                                                                                                                                        Li Jin

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