Accedmychevron_right11thchevron_rightmathchevron_rightTrigonometric Functions And Their Graphschevron_rightExercise 11.3

Questions

  1. Question 2

    The temperature TT in degrees Celsius of a certain city varies throughout the day according to the equation T(t)=132sin(π6tπ9)+15T(t) = \dfrac{13}{2}\sin\left(\dfrac{\pi}{6}t - \dfrac{\pi}{9}\right) + 15, where tt is the time in hours, with t=0t = 0 corresponding to midnight.

  2. Question 3

    A man on the top of a 100 m high light-house is in line with two ships on the same side of it, whose angles of depression from the man are 1717^\circ and 1919^\circ respectively. Find the distance between the ships.

  3. Question 4

    PP and QQ are two points in line with a tree. If the distance between PP and QQ be 30 m and the angles of elevation of the top of the tree at PP and QQ are 1212^\circ and 1515^\circ respectively, find the height of the tree.

  4. Question 5

    A giant Ferris wheel has a diameter of 60 feet. The lowest point of the wheel is located 6 feet above the ground. The wheel completes one full revolution every 80 seconds.

  5. Question 6

    A child is playing on a swing in a playground. The height h(t)h(t) of the swing seat above the ground (in metres) at time tt (in seconds) is modeled by the function: h(t)=1.5+1.2sin(3πt)h(t) = 1.5 + 1.2\sin(3\pi t).

  6. Question 7

    A carnival ride consists of a vertical wheel with a diameter of 40 feet. The centre of the wheel is 28 feet above the ground. The wheel rotates at a constant speed and takes 120 seconds to make one complete revolution. Model an equation that describes the height h(t)h(t) of a rider on the wheel as a function of time tt. How high is the rider from the ground after 90 seconds? At what times will the rider be 36 feet above the ground?

  7. Question 8

    Suppose the temperature TT in degrees Fahrenheit of Lahore city in a month of December throughout the day can be modeled by the equation: T=64+8sin(π12(t8))T = 64 + 8\sin\left(\dfrac{\pi}{12}(t - 8)\right), where tt is the time in hours. The temperature oscillates 8 degrees above and below an average temperature of 64 degrees.

  8. Question 9

    Suppose the population of a coastal city follows a sinusoidal pattern due to seasonal migration. The population of the city over the course of a year can be modeled by the equation: P(t)=70000+10000cos(π6tπ2)P(t) = 70000 + 10000\cos\left(\dfrac{\pi}{6}t - \dfrac{\pi}{2}\right), P(t)P(t) is the population at time tt (tt is the time in months, with t=0t = 0 corresponding to January 1st).