The Bay of Fundy
Date: 04/13/97 at 17:23:14 From: Nikita Bacchus Subject: Bay of Fundy Hi Dr. Math, The Bay of Fundy in Canada is reputed to have the largest tides in the world, with the difference between low and high water level being as much as 15 meters. Suppose at a particular point in the Bay of Fundy, the dept of the water, y meters, as a function of time, t, in hours since midnight on Jan 1, 1994, is given by y=y0+Acos[B(t-t0)] What is the physical meaning of y0? What is the value of A? What is the value of B? Assume the time between successive high tides is 12.5 hours. What is the physical meaning of t0?
Date: 04/14/97 at 10:20:03 From: Doctor Anthony Subject: Re: Bay of Fundy y0 is the water depth halfway between low and high water. A is the amplitude of the cos curve = 7.5 metres To find B we require that when t - t0 = 12.5 hours we are back to same value. So if B = 2.pi/12.5 = pi/6.25 this will make the cos curve repeat itself every 12.5 hours. We put B = pi/6.25 = 0.50265. The physical meaning of t0. When t = t0 we have y = y0 + A which is high water, and so t0 is the time of last high water. -Doctor Anthony, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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