# There are two kinds of applications we will study in section 4 ```Section 4-8
There are two kinds of applications we will study in section 4-8
1) Right triangle trigonometry (angle of elevation/depression
2) Sinusoids (Ferris wheel, harmonic motion)
ex. From the top of a 100 ft tall building a man observes a car
moving toward the building. If the angle of depression of the car
changess from 20 to 42 during the period of observation, how far
does the car travel?
Ex A patrol boat leaves port and averages 35 knots traveling for 2
hours on a course of 53 and then 3 hours on a course of 143
. What is the boat's bearing and distance from port.
Ex. A mass oscillating up and down on the bottom of a spring
can be modeled as harmonic motion. If the weight is displaced a
maximum of 5 cm, find a modelling equation if it takes 2 seconds
to complete one cycle.
Ex. A Ferris wheel 50 ft in diameter makes one revolution every
40 sec. If the center of the wheel is 30 ft above ground, create a
model of the height of a rider in terms of time. How long after
reaching the low point is the rider 50 ft above the ground?
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