题干

下列说法不正确的是

A:电场中某点电势与零电势点的选取有关,而电场中某两点间的电势差与零电势点选取无关

B:同一点电荷在电势高的地方电势能较大,在电势低的地方电势能较小

C:同一点电荷,电场力做正功,其电势能一定减小;电场力做负功,其电势能一定增加

D:同一点电荷在电场中任意两点间移动时,只要电场力做功相同,则两点间的电势差一定相同

上一题 下一题 0.0难度 选择题 更新时间:2011-03-25 10:24:54

答案(点此获取答案解析)

B

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    Differences are important and they should be respected. For example, many important people throughout history were considered different, such as Thomas Edison, Albert Einstein and Abraham Lincoln. They did great things, but some people thought they were strange because they had strong feelings about something. I can understand these people because I've been in that situation before many times.

    It all started in elementary school when I realized that I wasn't like everyone else. My mom says that I have a tendency to be obsessed(着迷)with certain subjects. Unfortunately, these subjects don't interest other kids of my age and they really don't interest my teachers. In fact, my kindergarten teacher said she would scream if I mentioned snakes or lizards one more time while she was teaching the days of the week. I would get into trouble for not paying attention and the teasing began.

    In the third grade, my teacher informed me that I have Asperger's Syndrome(症状). I said, “So what? Do you know that Godzilla's suit weighs 188 pounds?”

    Later, I asked my mom, “What's Asperger's Syndrome? Am I gonna die?” She said that it's like having blinders on, and that I can only see one thing at a time, and that it's hard to focus on other things.

    People also make fun of me for knowing facts about volcanoes, whales, tornadoes and many other scientific things. My mom says that she has been able to answer many questions on Jeopardy! just by listening to what I have to say, but I've even been laughed at for being smart.

    Maybe someday I'll become a gene engineer and create the real Godzilla. I can dream, Can't I?