关于曲线运动的速度，下列说法正确的是_刷题宝

题干

关于曲线运动的速度，下列说法正确的是（）

A：速度的大小与方向可能都在时刻变化

B：速度的大小不断变化，速度的方向不一定发生变化

C：速度的方向不断发生变化，速度的大小也一定发生变化

D：质点在某一点的速度方向是在曲线上这一点的切线方向上

上一题下一题 0.0难度选择题更新时间:2019-09-16 07:44:53

答案(点此获取答案解析）

A,D

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根据短文，选择正确答案。

An old tiger lives in the forest. He does not want to look for food now. He often tells other animals to bring him something to eat.

He see a monkey and says, “I am hungry, Monkey. Go to the village and bring me a fat pig.”

“Oh, Tiger,” says the monkey. “I cannot do that now. There is another tiger over there. He also wants a fat pig. He will not let me get anything for you to eat. I am afraid of him.”

“What?” cries the old tiger?“Show me that tiger. I will talk to him.”

“Come with me,” says the monkey.

The monkey and the tiger get to a bridge over the river.

“Now look down at the river,”says the monkey.

“Do you see the head, the white teeth and the large green eyes of a tiger?”

“Yes, I do.” Cries the old tiger, “I will eat him up”

With these words, the tiger jumps into the water.

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多云的夜晚气温比晴朗的夜晚气温高的原因是（　　）

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What do you do ____(on/in)Sunday ?

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