UCSB Science Line Does the size of the moon effect how big the ocean waves are? Question Date: 2016-08-31 Answer 1: Well, the oceans' waves are due to winds blowing across the surface of the ocean. These winds get the water near the very top moving in the direction of the wind and that is what creates waves near the shoreline. When the distance between the wave crests becomes longer than the DEPTH of the water, the waves BREAK; the moon has nothing to do with that. However, the MOON does generate the TIDES. The tides originate because relative to the center of the earth, the gravitational force of the moon is greater on the side towards the moon. BUT at the same time the gravitational pull on the solid earth on the opposite side is LESS than at Earth center; so, this effect gives us a high tide twice a day and a low tide twice a day. Answer 2:Yes it does. The gravitational force between the moon and the earth is mutual. And different places on earth will feel different gravitational force from the moon, due to their different distances from the moon. This seemingly tiny difference causes the tides on earth that we see every day. If the size (and weight) of the moon increases, the tide is expected to be bigger. Answer 3:While the size has something to do with it, what really affects the power of ocean's waves is the mass. If the Earth were to be floating through space with nothing around it, the water would totally be pulled towards the center due to the force of Earth's gravity, where we wouldn't see any waves. However, the moon has a large amount of mass that causes its own force on the earth. Since its much smaller, the moon doesn't deflect the Earth from it's orbit, but only pulls on the water on the surface of the Earth. This is due to the force of gravity from the moon to the earth, which is related directly to the mass of the Earth, the mass of the moon, and inversely to the squared distance between the objects (or simply M*m/r(2)). We see a factor of the radius between the objects, meaning the closer the two objects are, the greater force the Earth will feel, and, in turn, the greater the tides will be. Now, using this same reasoning, we can deduce that the sun would also cause a gravitational force on the ocean's waves. This is true, due to how massive the sun is compared to the Earth, but because how far away from us the star is, the effects on the tides are much smaller than that of the moon's. This is seen from the dependence on inverse distance (1/r(2)) in the gravitational force. Hope this answers your question!Click Here to return to the search form.    Copyright © 2020 The Regents of the University of California, All Rights Reserved. UCSB Terms of Use