Can anybody enlighten me on shockwaves?

Question

preferbly in layman terms that is easily understood, and please state suitable websites for references. Thanks

Answer 1

There's a couple of different definitions of a shockwave. Let's assume you're after the scientific version as opposed to the emotional definition.

A shockwave is the immediate after-effect of a large concussion caused by a sudden event like an explosion, a rapid expansion of a medium like air or water, or very sudden change within matter containing great force.

An excellent model of a shockwave are ripples in a pond when you toss a stone into it. The ripples eminate outward from ground zero, which is where the stone entered the water. What you see are disuptions in the water molecules and have an effect on everything around them like the duck trying to have a snooze if the sound of the splash didn't wake already wake him.

Picture this on a global scale perhaps when a large meteor or small asteriod strikes the ocean. The tidal wave or tsunami that hits the shores surrounding the point of impact is also considered a shockwave.

In an earthquake, the shockwave travels through a solid which is the Earth much the same way as the ripples in the pond after a huge concussion of interlocking plates of rock in the Earth suddenly snap against each other under stress and produce a massive jolt of energy. It is physically possible to see the land ripple as the shockwave moves outward and this is what destroys our buildings.

In an explosion, the shockwave travels through the air as a result of an extremely rapid expansion of the air molecules from the very sudden heat generated by a detonation. So if you witness a nuclear explosion a few miles away, the light reaches you instantaneously. You have a few seconds to take cover before the shockwave travelling through the air reaches you.

Shockwaves lose energy over distance due to resistance, just like the way the pond eventually becomes still and the duck can sleep finally sleep again.

The other definition of shockwave deals with emotions such as 'The news of the astronaut's erratic behavior has sent shockwaves throughout the space science community.'

For a more scientific answer see:

http://en.wikipedia.org/wiki/Shockwave

Answer 2

Shockwaves occur after any event which releases large quantities of energy in a short time, that is a shock. A large explosion sets off shock waves in air. A large earthquake sets off shockwaves in the land and sea. Shockwaves cause damage to property and people. Many buildings are not designed to withstand shockwaves beyond some magnitude.

Even a supersonic jet causes a sonic boom, which is a sort of shock wave and can damage life and property. Tsunami is a shock wave in the sea caused by an earthquake.

If you type the key words like Shock Waves, Tsunami, Earthquakes, Nuclear Explosion etc. you will get a lot of information.