题干

 小明在用单摆做动能和势能转化的实验中,感到小球往返摆动的时间很有规律。于是猜想,小球往返摆动一次的时间可能与小球的质量、摆长l以及摆动的幅度s有关。小明用右图所示的装置,对猜想进行探究。用一小球,使其摆动,记下小球往返摆动次数和所用的时间;在摆长不变的条件下,用质量不同

的小球,重复实验。小明经计算分析得出结论:在摆长不变的条件下,小球往返摆动一次所用的时间与小球的质量无关。

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    Do you look like your name? Scientists say there's a good chance you do.

This comes from a new study published in a magazine. Researchers from Israel found that our given names may have something to do with our facial (面部的) appearances.

    Lead writer Yonat Zwebner of a university, along with her team, did eight different experiments (实验) in Israel and France. The different experiments were set up to answer two main questions: whether people can correctly guess a person's name based only on a photo of a face and what is behind this matching effect.

    During the experiments, researchers asked students to look at photos of people's faces and guess each person's name from a list of four choices. They correctly guessed the right name 38 percent of the time, which was better than the 25 percent of a random (随机的) guess.

    What's more, when the faces the students looked at came from within their own country, they were able to best match the faces to the names. French students were better at matching only French names and faces while Israeli students were better at matching only Hebrew names and Israeli faces.

    Researchers believe it is possible that people change their appearances without paying attention to it, to match their names. One study especially backed up this idea, showing that a hairstyle, something that can be changed by people easily, was enough to guide others in correctly guessing their names.

    “Earlier research has shown there are cultural stereotypes (偏见) carried by names, including how someone should look. For example, people are more likely to imagine a person named Bob to have a rounder face than a person named Tim. We believe these stereotypes can, over time, influence people's facial appearances,” Zwebner said.

    The results of the experiments may even make parents think twice when choosing a name for their children.

    “If a name can influence appearance, it can influence many other things. This research opens an important direction that may suggest how parents should consider better the names for their children,” said Zwebner, who recently had a baby herself.

    “As parents, it was really difficult for us to name our 12-day-old daughter as we know the meanings of names.”