Suppose that the length of time between consecutive high tides is approximately 12.5 hours. According to the National Oceanic and Atmospheric administration, on Saturday, June 28, 1997, on a certain beach, high tide occurred at 4:38AM (4.6333 hours) and low tide occurred at 11:08AM (11.1333 hours). Water heights are measured as the amounts above or below the mean lower low water. The height of the water at high tide was 8.5 feet and the height of the water at low tide was -0.9 feet.
Find a sinusoidal function of the form y = Asin(omega x - phi) + B that fits the data
2007-12-16 08:57:14 · 1 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
B is just the average of the high and low figures 8.5 and -.9.
A is just 1/2 the difference between the high and low figures 8.5 and -.9, which is the same as the difference between either one of them and B.
omega * pi = 11.1333 - 4.6333.
omega * 4.6333 - phi = pi/2. So solve for omega first and then phi.
pi = 180 degrees, alternatively, if you're working in degrees instead of radians.
2007-12-16 11:48:02 · answer #1 · answered by Curt Monash 7 · 0⤊ 0⤋