徐化同学: 你认为硬币能浮在水面上,是由于水面有张力而成一层薄膜,这基本上是对的。只是水面实际上没有“薄膜”。表面张力是物质的共有性质之一。它实际上是物质分子之间的引力在物质表面的反映。水面、是水和空气的接触面,水最表面的那层分子,下面受水分子的吸 Xu students: Do you think the coins can float on the water surface is due to the tension of the water into a film, which is basically right. Only the water is actually no “film.” Surface tension is one of the common properties of matter. It is actually a reflection of the attraction between material molecules on the material surface. Water surface is the contact surface of water and air, the water surface layer of molecules, the following by the water molecules of the suction