Tides go up and down in a 14.8-hour period.?

Question

Tides go up and down in a 14.8-hour period. The average depth of a certain river is 7 m and ranges from 3 to 11 m. The variation can be approximated by a sine curve. Write an equation that gives the approximate variation y, if x is the number of hours after midnight and high tide occurs at 8:00 a.m.

Answer 1

omega = 2*pi*f, use f=(1/14.8)hrs^-1

The amplitude of the change is 4.

The equation is h = 7m + 4sin(omega*t-omega*8hrs+pi/2 ) where t is in hours, the angles in radians.