题干

以下列举了几种物体的运动,若都忽略空气对运动物体的阻力,则其中不遵守机械能守恒定律的是 (     )

A:物体沿着斜面匀速下滑

B:物体由光滑斜面顶端滑到斜面底端

C:在竖直方向弹簧振子所做的简谐运动

D:铅球运动员抛出的铅球从抛出到落地前的运动

上一题 下一题 0.0难度 选择题 更新时间:2018-01-11 01:09:41

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A

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    Housework is a frequent source of disputes (争论) between lazy husbands and their hard-working wives, but women have been warned not to expect men to pull their weight any time soon.

    A study from Oxford University has found that men are unlikely to be doing an equal share of housework before 2050. Mothers, the researchers warned, will continue to shoulder the burden of childcare and housework for the next four decades, largely because housework such as cleaning and cooking is still regarded as“women's work”.

    The gap between the amount of time men and women spend on housework has narrowed slowly over the past 40 years. But it will take another four decades before true housework equality is achieved, the study concluded. The research found that in the Nordic countries, the burden of housework is shared more equally between men and women. In the UK, women spend an average of four hours and forty minutes each day on housework, compared with two hours and twenty-eight minutes for men. This is an improvement from the 1960s, when British women typically spent six hours a day on housework, while men spent just 90 minutes every day.

    But progress towards housework equality appears to be slowing in some countries. Dr Oriel Sullivan, a research reader from Oxford's Department of Sociology, said, “we've looked at what is affecting the equality in the home, and we have found that certain tasks seem to be given according to whether they are viewed as ‘men's work' or ‘women's work'.”Dr Sullivan said cultural attitudes taught at school may be responsible for the views of housework. “At school it is much easier for a girl to be a tomboy, but it is much more difficult for a boy to enjoy baking and dancing,” she said.

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