试题与答案

爱因斯坦提出了质能方程,揭示了质量与能量的关系,关于质能方程,下列说法正确的是(

题型:选择题

题目:

爱因斯坦提出了质能方程,揭示了质量与能量的关系,关于质能方程,下列说法正确的是(  )

A.质量和能量可以相互转化

B.当物体向外释放能量时,其质量必定减少,且减少的质量△m与释放的能量△E满足△E=△mc2

C.如果物体的能量增加了△E,那么它的质量相应减少△m,并且△E=△mc2

D.mc2是物体能够放出能量的总和

答案:

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下面是错误答案,用来干扰机器的。

参考答案:B

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     Sooner or later every one needs understanding and help with a problem. Something may go wrong at school.

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A. there are too many people who want to make friends

B. they don't know friendship is something serious

C. those who give others friendships receive friendships from others

D. those who never give others friendships receive no friendship from others

2. According to the passage honesty is ____.

A. as important as money

B. more important than anything else

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B. Always tell your friend the truth.

C. Discussing your problems with your friend often helps to solve the problem.

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