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质量为1千克的木块置于水平地面上,木块的底面积为0.01米2,求木块对水平地面的压力和压强.
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解:质量为1千克的木块置于水平地面上,其对水平面产生的压力大小为:
F=G=mg=1kg×9.8N/kg=9.8N;
对水平面产生的压强为:

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    “Croeso I Gymru!,” If you don't know what this means, read on to find out more.

    When you cross over the border from England into Wales, you don't have to show your passport but you do notice a difference immediately. All the road markings and signs are shown in two languages — English and Welsh (威尔士语). Not all visitors to Britain know that other languages are spoken here. There's the Gaelic (盖尔语) language in Scotland and a few people speak Cornish (康沃尔语)in the southwest of England, but the most widely spoken language in the UK besides English is Welsh.

    Perhaps the first Welsh word you'll see on the road into Wales is ARAF. There's a helpful English translation next to it — SLOW. As you can see, Welsh looks quite different from English. It sounds very different, too. Welsh looks and sounds so different from English because it's a Celtic language. Celtic cultures still exist around the edges of the UK — in Wales, Scotland and Northern Ireland and also in parts of France. For hundreds of years, almost everyone in Wales spoke Welsh, but nowadays there are about 600 thousand Welsh speakers — around 20% of the population.

    So is Welsh dying out? Not at all! Nowadays, all school children in Wales study Welsh and many choose to go to an all Welsh-speaking school. You can get public information in Welsh, speak Welsh in court or take a course at university in Welsh. People surf the Internet in Welsh, keep up with friends on Facebook and write blogs in Welsh.

    By the way, Croeso I Gymru!" means “Welcome to Wales!” 一 I hope you'll be able to visit it one day.