# The Naked Scientists Forum

### Author Topic: why are ripples always circular?  (Read 4588 times)

#### paul.fr

• Guest
##### why are ripples always circular?
« on: 04/06/2007 18:45:18 »
if i throw a ball in to the pond, the ripples are round. Well ok, my ball was round. But if i throw a house brick the ripples are still round even though the brick is not! why is that?

#### Bored chemist

• Neilep Level Member
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##### why are ripples always circular?
« Reply #1 on: 04/06/2007 19:41:28 »
All the ripples start out from (pretty nearly) the same place at the same time. Waves in water travel at a constant speed (it's about 3 feet a second IIRC) after 1 second the waves are all 3 feet from the initial point and the only way they can all be the same distance from a given point is to be a circle (strictly, they could bo on a sphere but that's a bit silly)

#### daveshorts

• Moderator
• Neilep Level Member
• Posts: 2583
• Physics, Experiments
##### why are ripples always circular?
« Reply #2 on: 05/06/2007 08:56:43 »
If you throw a brick in water, When the ripple starts off it will be oblong. In one direction it will be about 6 inches by 3 inches. 1 second later the ripples will have expanded by 3 feet so the total ripple will be 6 foot 6 inches by 6 foot 3 inches. After 2 seconds, 12 foot 6 inches by 12foot 3 inches etc.

So basically it is never perfectly circular, but the errors from a circle stay the same size as the ripples expand rapidly.

#### Ashtari

• Jr. Member
• Posts: 46
• The truth will set you free
##### why are ripples always circular?
« Reply #3 on: 06/06/2007 11:00:31 »
Paul.fr

Click on this and see what you wanted to know.  [:X]

http://www.heartcoherence.com/starmother/DynaRainbow_MPhi.htm [nofollow]

Ashtari

#### The Naked Scientists Forum

##### why are ripples always circular?
« Reply #3 on: 06/06/2007 11:00:31 »