Q:

What happens in a nuclear meltdown?

A:

Quick Answer

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.

  Know More
What happens in a nuclear meltdown?
Credit: Björn Meyer E+ Getty Images

Full Answer

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

Related Questions

  • Q:

    How do nuclear reactors work?

    A:

    Nuclear plants use a process called fission to generate enough energy to boil large amounts of water and turn it into steam. The steam then spins turbines that generate electricity, which utility companies distribute to homes and businesses. Fission involves splitting a uranium atom within the nuclear reactor.

    Full Answer >
    Filed Under:
  • Q:

    How does a nuclear power station work?

    A:

    Nuclear power stations generate electricity through the fission, or splitting, of uranium atoms inside the reactor core, which generates extreme amounts of heat. The core is surrounded with water, which boils due to the heat, creating steam that is then used to drive a turbine to create electricity.

    Full Answer >
    Filed Under:
  • Q:

    What happens when warm air rises?

    A:

    Warm air constantly changes elevations in the atmosphere, which leads to harsh weather conditions such as thunderstorms, hurricanes, tornadoes and windy conditions. Poor weather conditions are the direct result of air rising after it is heated up by warm ocean currents.

    Full Answer >
    Filed Under:
  • Q:

    What happens to a balloon if placed in cold water and why?

    A:

    When an inflated balloon is placed in cold water, it shrinks. This happens because the air inside the balloon occupies a smaller volume when the temperature is decreased, thus causing the walls of the balloon to collapse.

    Full Answer >
    Filed Under:

Explore