Sound waves help the special effects team on Jurassic Park Movie

photo credit: Scott Kinmartin via photopin cc

Most of us have seen the Jurassic park Movies; Do you remember the scene in the first film when the dinosaurs are introduced for the first time? It is a very powerful scene… they are in the jeep and sudden the rear view mirror starts to shake and the water in some drinking cups, sitting in cup holders, starts to vibrate and form circular wave patterns.  I think it is an excellent scene… building up the idea of something big approaching using very simple visual effects. These effects were not simple to achieve however, it seems the special effects department were baffled as to just how to get the exact ripple patterns in the water that they required.

Eventually inspiration struck as Michael Lantieri (special effects department) sat at home strumming a guitar and suddenly noticed the effect the sound was having on a glass of water… it was his Eureka moment.  Next day he took the idea to work and finally they nailed it! They got the water patterns they desired by placing guitar strings under the dashboard and getting someone to pluck the correct string!

Check out the story in this YouTube clip.

This is a really easy experiment to try at home or in your school… all you need is a guitar, a plastic cup and some water.  Place the guitar on a flat surface, half fill the plastic cup with water and sit it on the body of the guitar (i.e. the wider flat part at the base, not directly on the strings) and start plucking away.  With a little bit of experimentation you see ripple patterns form in the water as you pluck the strings.

Move the cup around a little to see if you can get different effects, or try with more or less water in the cup.  Do you find lower or higher sounds give a better result? Does plucking of one particular string work best or how does it compare to plucking them all together?

Have fun with this one and remember to let me know if you try it out at home or in your school.