题干

两个用丝线悬挂着的硬泡沫塑料小球,发生相互作用时的情况如图所示,则它们的带电情况可能是(   )

A:两球一定带同种电荷

B:两球一定带异种电荷

C:两球都不带电

D:两球可能带异种电荷,也可能一个球带电而另一个球不带电

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D

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    More student than ever before are taking a gap-year (间隔年)before going to university.It used to be called the “year off” between school and university.The gap-year phenomenon originated(起源) with the months left over to Oxbridge applicants between entrance exams in November and the start of the next academic year.

    This year, 25,310 students who have accepted places in higher education institutions have put off their entry until next year, according to statistics on university entrance provided by University and College Admissions Service (UCAS) .

    That is a record 14.7% increase in the number of students taking a gap year. Tony Higgins from UCAS said that the statistics are good news for everyone in higher education. “Students who take a well-planned year out are more likely to be satisfied with, and complete, their chosen course. Students who take a gap year are often more mature and responsible,” he said.

    But not everyone is happy. Owain James, the president of the National Union of Students(NUS), argued that the increase is evidence of student had ship – young people are being forced into earning money before finishing their education. “New students are now aware that they are likely to leave university up to £15,000 in debt. It is not surprising that more and More students are taking a gap year to earn money to support their study for the degree.NUS statistics show that over 40% of students are forced to work during term time and the figure increases to 90% during vacation periods,”he said.