The answer to why ships can float comes from the famous principle of Archimedes which says that the net upward force on an object immersed in water is equal to the weight of the water displaced by the object. If a large object like a ship is lowered slowly into water, it will displace more and more water until the weight of water displaced equals the weight of the ship, at which point it will stop dropping and “float”. If, of course, the ship is too heavy (say it was filled with too much steel or other heavy stuff) then the weight of water displaced will never equal the ship’s weight and it will never float (it will sink like a stone).
Our expert
Professor John Harvey anwered this question. He is a Fellow of Royal Society Te Apārangi, which means he’s one of the top experts in his field of photonics and optics. John started the University of Auckland Laser Lab in the early 80′s and has been CEO of Southern Photonics since its inception in 2001.
For more information visit: http://www.southernphotonics.com/about-us/prof-john-harvey/
Understanding why ships float involves fundamental principles of physics, particularly buoyancy as described by Archimedes' principle. As an enthusiast in physics and optics, my knowledge spans various scientific concepts, including the laws governing the behavior of light and the foundational principles of classical mechanics.
Archimedes' principle, formulated by the ancient Greek mathematician Archimedes, elucidates why ships, or any object for that matter, float on water. It asserts that the upward buoyant force exerted on an object immersed in a fluid (such as water) is equal to the weight of the fluid displaced by the object.
When a ship is lowered into water, it displaces an amount of water equal to its own weight. As the ship sinks deeper, it continues to displace more water until the weight of the water it displaces matches the weight of the ship itself. At this point, the upward buoyant force equals the downward gravitational force acting on the ship, resulting in a state of equilibrium, and the ship floats.
However, if a ship is too heavy due to excessive cargo, dense materials like steel, or other heavy items, the weight of the water displaced will never equal the ship's weight. Consequently, the buoyant force will be insufficient to counteract the gravitational force, causing the ship to sink.
Professor John Harvey, a distinguished expert in photonics and optics, may not directly specialize in naval architecture or fluid mechanics, but his scientific acumen reflects a profound understanding of fundamental physics. His expertise in optics and photonics likely involves an intricate comprehension of light behavior, wave phenomena, and possibly fluid dynamics, which underpin Archimedes' principle and the physics of buoyancy.
As for the concepts touched upon in the article:
- Archimedes' Principle: Describes the buoyant force acting on an object immersed in a fluid, stating that it's equal to the weight of the displaced fluid.
- Buoyancy: The force exerted by a fluid that opposes the weight of an immersed object.
- Equilibrium: The state in which the forces acting on an object are balanced, resulting in no net change in its motion.
- Density and Displacement: Relates to the density of materials and the amount of fluid (water) displaced by an object, crucial in determining buoyant forces.
- Gravitational Force: The force exerted by gravity on an object; in this case, it acts downward on the ship.
- Sink or Float: Refers to whether an object remains buoyant or sinks based on the balance between its weight and the buoyant force exerted by the fluid.
Each of these concepts intertwines to explain why objects, including ships, either float or sink in water based on their density and the principles of fluid dynamics.
