According to the Scientific American, during a nuclear meltdown, core material overheats, either due to a runaway reaction or loss of coolant. The extreme temperatures can cause damage to the reactor, partially melt the nuclear fuel and contaminate any remaining coolant with radioactive material. In addition, some reactor designs use pressure vessels, and a meltdown can increase pressure enough to cause an explosion or release radioactivity from the containment vessel.Continue Reading
The Scientific American explains that one of the major dangers of a nuclear meltdown is the possibility of a runaway reaction. Under normal circumstances, the core material is kept in contact with neutron-absorbing control rods in order to slow down or stop the reaction, as necessary. A meltdown can damage the control mechanism, preventing these rods from engaging, or it can melt enough nuclear fuel together to create a self-sustaining reaction. In these cases, the fuel can continue to produce heat and dangerous radioactivity long after the initial accident ends.
Wikipedia notes that the most infamous nuclear meltdown occurred on April 26, 1986, when the Chernobyl Nuclear Power Plant suffered a catastrophic failure. A coolant failure led the core to build up heat to dangerous levels, creating a steam explosion that blew off the roof of the reactor. The explosion spread radioactive material over a large area, contaminating the surrounding city and countryside for decades.Learn more about Physics
Light bends as its speed changes when the light beam crosses the boundary from one material into the next. When light bends, it is called refraction. The direction it bends is determined by the speed at which it crosses the boundary.Full Answer >
Bouncy balls bounce high because the material of the ball is extremely elastic and can convert the kinetic energy from the fall into potential energy and back again with very little loss in momentum. Bouncy balls are used in many physics classrooms because they aptly demonstrate conservation of momentum through a highly elastic collision.Full Answer >
Also called material derivative, substantial derivative computes time’s rate of change of any quantity such as velocity or temperature for a portion of any material that moves with velocity. Flow patterns, which include velocity, temperature and pressure among others, are defined as a function of time and space.Full Answer >
The strength of the interatomic and intermolecular bonds in a material as well as the temperature and pressure determine the state of matter that it assumes. Material states at different temperatures and pressures are represented by phase diagrams.Full Answer >