Waves and Sound (20 Days)
Enduring Understanding: Any disturbance that propagates through a medium is a mechanical wave. These disturbances are a result of energy input from a source; and, the resultant motion is oscillatory. Energy conservation is used to study and explain the properties of waves in these media. Many other phenomena which are periodic in nature, such as a mass on a spring or a pendulum’s motion, can also be understood using energy conservation.

Essential Questions
What is simple harmonic motion?
(2 days)
What factors affect simple harmonic motion of a pendulum and a mass-spring system?
(3 days)
SC.912.P.10
Differentiate among the various forms of energy and recognize that they can be transformed from one form to others.
A. Energy is involved in all physical and chemical processes. It is conserved, and can be transformed from one form to another and into work.
E. Waves are the propagation of a disturbance. They transport energy and momentum but do not transport matter.

Student defines, describes, and analyzes simple harmonic motion. o Student recognizes any motion which exhibits a repeated “back-and-forth” demonstrates simple harmonic motion. o Student identifies and relates variables affecting period, frequency, and amplitude. o Student analyzes a problem to compute the restoring force in an elastic spring using
Hooke’s Law.
𝐹 = −𝑘𝑥 o Student analyzes, sketches, and solves for an unknown in a vertically hanging elastic spring.
𝐹 𝑠𝑝
= 𝐹 𝑔 o Student will analyze variables and calculate the period of a pendulum. 𝑙
𝑇 = 2𝜋√ 𝑔 o Student will analyze variables and calculate the period of a mass-spring system.
𝑇 = 2𝜋√ 𝑚 𝑘

What is a mechanical wave? (1 day)
What distinguishes one mechanical wave from another? (1 day)
How do the different characteristics used to measure waves relate to each other?
(3 days)
Why does the speed of a wave change passing from one medium to another?
(1 day)
What determines whether an incident wave pulse striking a boundary reflects
SC.912.P.10.20
Describe the measurable properties of waves and explain the relationships among them and how these properties change when the wave moves from one medium to another.
LA.910.2.2.3
The student will organize information to show understanding or relationships among facts, ideas, and events (e.g., representing key points within text through charting, mapping, paraphrasing, summarizing, comparing, contrasting, or outlining.)

Student will define and identify characteristics of mechanical waves.

Student will distinguish properties and cite examples of transverse, longitudinal, and surface waves. o Student will describe the vibration of particles in relation to the wave’s motion of a transverse, longitudinal, and surface wave. o Student will demonstrate how to propagate a transverse and longitudinal wave.

Student will analyze characteristics used to measure and describe waves, such as speed, amplitude, wavelength, period, and frequency. o Student will identify and label parts of a wave.

Student will analyze a problem and calculate speed, wavelength, period, or frequency of a wave. 𝑓 =
1
𝑇 𝑣 = 𝜆𝑓

Student will relate a wave’s speed to the properties of the medium in which the wave travels.

Student will apply concepts to predict how a wave pulse reflects at boundaries.

inverted or not? (1 day)
How can the principle of superposition be used to describe wave interference in a variety of situations? (2 days)
What are characteristics of a sound wave?
(3 days)
Why does the speed of a sound wave change as it travels through different media or changes in the properties of the same media? (1 day)

Student will apply the principle of superposition to the phenomenon of interference. o Student will determine constructive or destructive interference when two individual pulses meet. o Student will apply the principle of superposition and wave reflection with nodes and antinodes of a standing wave. o Student will draw a resultant wave from combining two individual interfering waves using the principle of superposition.
SC.912.P.10.20

Student will compare the properties that sound waves share with other waves. o Student recognizes sound is a longitudinal (compressional) wave. o Student recognizes an energy source is required to generate sound. o Student recognizes an echo is a reflected wave. o Student will apply concepts of constructive and destructive interference to intensity of sound. o Student will qualitatively compare loudness of different sounds. o Student applies concepts to describe how the properties of the media through which a sound wave travels affects its speed.

What is the Doppler Effect and how does it occur? (2 days)
SC.912.P.10.21
Qualitatively describe the shift in frequency in sound or electromagnetic waves due to the relative motion of a source or a receiver.

Students will recognize the Doppler Effect explains that the difference in perceived frequency is related to the relative velocity of source and detector.

Students will recall perceived frequency is higher when source and detector are moving together (blueshift), and lower when they are moving apart (redshift).