May 22, 1998 transcript #: 234-5
Subject(s): moon, tide, centrifugal force, gravity
Title: LISTENER QUESTION: MOON & TIDE
Hi, Im Dave Thurlow for The Weather Notebook. Today I have a question from one of our listeners:
"Hello, my name is Eileen Keim, from Concord, NH. I have a question. I've seen those little diagrams in schoolbooks explaining how the tide rises in response to the moon. And it shows a high tide both on the side directly under the moon and the side directly opposite the moon. And I suddenly started to wonder, how come? Why should there be a high tide directly opposite the moon instead of just a general high tide on the side with the moon attraction. I'd love it if you could answer that one for me.
Well that is a good question you guys know the answer to that? Great thats The Weather Notebook research staff. Well, ok. Ill just look it up in some books Ive got here just a second lets see Oh ya here we go. The ocean tides are caused by three things -- the moon, a little bit by the sun, and by centrifugal force created by the earth and moon spinning in tandem. The moons gravity forces the ocean toward it on the side of the earth facing the moon, but centrifugal force of the spinning earth/moon system forces the ocean to bulge on the side of the earth opposite the moon. Simply its gravity and centrifugal force that lift the ocean waters skyward on all sides of the planet. If you have a weather question please call us a 1-888-724-6001, or search for answers on our website at mountwashington.org/notebook.
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