KnowHOW team explains: Water drops, or, for that matter, the drops of any other liquid, are spherical in shape due to a phenomenon called surface tension. In a liquid this acts on the surface of a freely falling drop to minimise its area. Compared to other objects, such as an ellipsoid an egg-shaped object , the ratio between the surface area and the volume is minimum in case of a sphere.
Surface tension, in simpler terms, is the tendency of the surface of a liquid to behave like a stretched membrane. This results from the attraction between the molecules in the liquid. Molecules at the surface of any liquid, unlike the ones in the interior, do not experience a uniform attractive force.
The functional relationship between Zdr and Do is developed from the underlying microphysical relation between the mean axis ratio of raindrops and their size.
This shape size relation can potentially be perturbed in the presence of raindrop oscillations. Grogucci et al. Once Do is retrieved, then the other parameters of the DSD can be retrieved such as No of the normalized form of a Gamma distribution Gorgucci et al. The statistics of the parameter Do, Nw are important in the development of algorithms. Skip to main content. The Shape of a Raindrop. Formal , 9 - This article teaches how a drop of rain changes shape as it falls through the atmosphere.
Water molecules want to cling to each other. At the surface, however, there are fewer water molecules to cling to since there is air above thus, no water molecules. This results in a stronger bond between those molecules that actually do come in contact with one another, and a layer of strongly bonded water see diagram.
This surface layer held together by surface tension creates a considerable barrier between the atmosphere and the water. In fact, other than mercury, water has the greatest surface tension of any liquid. Source: Lakes of Missouri. Within a body of a liquid, a molecule will not experience a net force because the forces by the neighboring molecules all cancel out diagram. However for a molecule on the surface of the liquid, there will be a net inward force since there will be no attractive force acting from above.
This inward net force causes the molecules on the surface to contract and to resist being stretched or broken.
Thus the surface is under tension, which is probably where the name "surface tension" came from. Source: Woodrow Wilson Foundation. Due to the surface tension, small objects will "float" on the surface of a fluid, as long as the object cannot break through and separate the top layer of water molecules. When an object is on the surface of the fluid, the surface under tension will behave like an elastic membrane. Water striders are able to walk on top of water due to a combination of several factors.
Water striders use the high surface tension of water and long, hydrophobic legs to help them stay above water. Water striders use this surface tension to their advantage through their highly adapted legs and distributed weight. The legs of a water strider are long and slender, allowing the weight of the water strider body to be distributed over a large surface area.
The legs are strong, but have flexibility that allows the water striders to keep their weight evenly distributed and flow with the water movement. Hydrofuge hairs line the body surface of the water strider. Source: Georgia State University. Looking at water, you might think that it's the most simple thing around. Pure water is practically colorless, odorless, and tasteless.
But it's not at all simple and plain and it is vital for all life on Earth. Where there is water there is life, and where water is scarce, life has to struggle or just "throw in the towel. Adhesion and cohesion are important water properties that affects how water works everywhere, from plant leaves to your own body. Just remember
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