题目

阅读理解 Sweet or salty? What kind of tastes do you like? If like me, you have a sweet tooth and you probably can't resist eating cakes, biscuits or chocolate and will sweeten your tea or coffee with spoonfuls of sugar-delicious! But the taste makes it very easy to ignore the warnings that too much of the white stuff（东西）is bad for our health. Consuming sugar is an addiction-the more we eat, the more we want. Today's processed food, like ready meals, is related to the stuff and many fizzy（起泡的）drinks contain seven teaspoons of sugar in just one can. In the UK, statistics sh如下图所示，用50N的水平推力将20N重的物体A压在竖直墙壁上，物体A与墙的接触面积为0.01m2，则物体对墙的压强为多大？ 5×103Pa 【解析】物体对墙的压力是50N,受力面积S＝0.01m2 则P＝＝5000Pa