题目内容

如下图所示，一根轻弹簧下端固定，竖立在水平面上。其正上方A位置有一只小球。小球从静止开始下落，在B位置接触弹簧的上端．在C位置小球所受弹力大小等于重力，在D位置小球速度减小到零。
下列对于小球下降阶段的说法中，正确的是______。

A. 在B位置小球动能最大
B. 在C位置小球动能最小
C. 从A→D位置小球重力势能的减少小于弹簧弹性势能的增加
D. 从A→C位置小球重力势能的减少大于小球动能的增加

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How long has Bryant been wearing No 8？

A. Since he started to play basketball.
B. For ten seasons.
C. Since he entered high school.
D. Since he left the Lakers.

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如图，在一长直导线L中载有恒定电流I1，ABCD为一刚性矩形线圈，与L共面，且AB 边与L平行.矩形线圈中载有恒定电流I2，则线圈AB边和CD边受到的安培力的方向分别为()

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Which of the following is NOT a speculation about Bryant’s motive to change his number,according to this passage？

A. He wants to leave his past behind and have a fresh start.
B. He wants to compare himself to Jordan.
C. He wants to earn more money.
D. He wants to show that he is a man of great importance.

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Which type of robot is NOI mentioned in the last paragraph？

A. Maggot-like robots.
B. Snake-like robots.
C. Ball-shaped robots.
D. Chair-shaped robots.

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A. 在B位置小球动能最大 B. 在C位置小球动能最小 C. 从A→D位置小球重力势能的减少小于弹簧弹性势能的增加 D. 从A→C位置小球重力势能的减少大于小球动能的增加

How long has Bryant been wearing No 8？

如图，在一长直导线L中载有恒定电流I1，ABCD为一刚性矩形线圈，与L共面，且AB 边与L平行.矩形线圈中载有恒定电流I2，则线圈AB边和CD边受到的安培力的方向分别为()

Which of the following is NOT a speculation about Bryant’s motive to change his number,according to this passage？

Which type of robot is NOI mentioned in the last paragraph？

A. 在B位置小球动能最大
B. 在C位置小球动能最小
C. 从A→D位置小球重力势能的减少小于弹簧弹性势能的增加
D. 从A→C位置小球重力势能的减少大于小球动能的增加