浮力是使船和沙滩球漂浮在水面上的力量。术语“浮力”是指流体（液体或气体）施加在部分或完全浸没在流体中的物体上的向上的力。浮力也解释了为什么我们可以比在陆地上更容易地将物体抬升到水下。根据罗马建筑师维特鲁威的说法，希腊数学家和哲学家阿基米德在公元前3世纪首次发现了浮力。同时对Syracuse的King Hiero II提出的问题感到困惑。希罗国王怀疑他的金冠是用花圈制成的，实际上并不是纯金制成的，而是金银混合物。据说，在洗澡时，阿基米德注意到他越沉入浴缸，水流出的越多。他意识到这是他的困境的答案，并在哭“Eureka！”时冲回家（“我找到了！”）然后他制作了两个物体 – 一个金币和一个银子 – 与皇冠的重量相同，然后将每一个放入装满水的边缘的容器中。因此，阿基米德证明他的王冠确实含有银。虽然这个故事说明了浮力的原理，但它可能是一个传说。阿基米德斯观察到，银质量导致更多的水流出船只而不是黄金。接下来，他观察到他的“金”皇冠使得更多的水流出血管而不是他创造的纯金物体，即使这两个皇冠的重量相同。阿基米德从未自己写过故事。此外，在实践中，如果确实将少量的银交换为黄金，则移位的水量太小而无法可靠地测量。在发现浮力之前，人们认为物体的形状决定了它是否会漂浮。浮力来自静水压力的差异 – 静态流体施加的压力。放置在流体中较高的球将比进一步向下放置的球经受更少的压力。这种净力 – 无论物体的形状如何都指向上方 – 是浮力。静水压力由P = rgh给出，其中r是流体的密度，g是由于重力引起的加速度，h是流体内的深度。静水压力不依赖于流体的形状。这是因为当流体更深时，有更多的流体，因此更多的重量作用在球上。因此，物体顶部的压力弱于底部的压力。可以使用公式Force = Pressure x Area将压力转换为力。有一个向上的净力。
Buoyancy is the force that enables boats and beach balls to float on water. The term buoyant force refers to the upward-directed force that a fluid (either a liquid or a gas) exerts on an object that is partially or completely immersed in the fluid. Buoyant force also explains why we can lift objects underwater more easily than on land. According to the Roman architect Vitruvius, the Greek mathematician and philosopher Archimedes first discovered buoyancy in the 3rd century B.C. while puzzling over a problem posed to him by King Hiero II of Syracuse. King Hiero suspected that his gold crown, made in the shape of a wreath, was not actually made of pure gold, but rather a mixture of gold and silver. Allegedly, while taking a bath, Archimedes noticed that the more he sank into the tub, the more water flowed out of it. He realized this was the answer to his predicament, and rushed home while crying “Eureka!” (“I’ve found it!”) He then made two objects – one gold and one silver – that were the same weight as the crown, and dropped each one into a vessel filled to the brim with water. Thus, Archimedes demonstrated that his crown indeed contained silver. Though this tale illustrates the principle of buoyancy, it may be a legend.Archimedes observed that the silver mass caused more water to flow out of the vessel than the gold one. Next, he observed that his “gold” crown caused more water to flow out of the vessel than the pure gold object he had created, even though the two crowns were of the same weight. Archimedes never wrote down the story himself. Furthermore, in practice, if a tiny amount of silver were indeed swapped for the gold, the amount of water displaced would be too small to reliably measure. Prior to the discovery of buoyancy, it was believed that an object’s shape determined whether or not it would float. The buoyant force arises from differences in hydrostatic pressure – the pressure exerted by a static fluid. A ball that is placed higher up in a fluid will experience less pressure than the same ball placed further down. This net force – which points upwards regardless of the object’s shape – is the buoyancy force. The hydrostatic pressure is given by P = rgh, where r is the density of the fluid, g is acceleration due to gravity, and h is the depth inside the fluid. The hydrostatic pressure does not depend on the shape of the fluid. This is because there is more fluid, and therefore more weight, acting on the ball when it is deeper in the fluid. Thus, the pressure at the top of an object is weaker than the pressure at the bottom. Pressure can be converted to force using the formula Force = Pressure x Area. There is a net force pointing upward.