问题
不定项选择
有两个物体都做加速度恒定的变速直线运动，则以下说法中正确的是
①经过相同的时间，速度变化大的物体，它的加速度一定大；
②若初速度相同，则末速度大的物体加速度一定大；
③若加速度相同，初速度大的物体其末速度一定大；
④在相同时间内，加速度大的物体其速度变化必然大。[ ]
A．①②
B．③④
C．①④
D．②③
答案
答案：C
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有两个物体都做加速度恒定的变速直线运动，则以下说法中正确的是
①经过相同的时间，速度变化大的物体，它的加速度一定大；
②若初速度相同，则末速度大的物体加速度一定大；
③若加速度相同，初速度大的物体其末速度一定大；
④在相同时间内，加速度大的物体其速度变化必然大。[ ]
A．①②
B．③④
C．①④
D．②③
答案：C
| 完形填空。 | ||||
| Zhang Jun is a Chinese 1 . He is not young, but he is not 2 . He is thirty-nine. He has a daughter. 3 name is Zhang Li. She is 4 . 5 is a Chinese girl. And she is a student. She 6 very lovely (可爱的). She is in 7 Three, Grade One. She likes 8 because (因为) she likes the sky (天空). And she 9 dance. Mr Zhang teaches English. 10 his class, there are forty-two 11 . They are all 12 students. His wife (妻子), 13 Zhang, is a teacher, too. Today is Sunday. They needn't (不必) go to 14 . 15 is free (有空) in Mr. Zhang's family. | ||||
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