In this lesson, students learn about sound. Girls and boys are introduced to the concept of frequency and how it applies to musical sounds.

Psychology is designed to meet scope and sequence requirements for the single-semester introduction to psychology course. The book offers a comprehensive treatment of core concepts, grounded in both classic studies and current and emerging research. The text also includes coverage of the DSM-5 in examinations of psychological disorders. Psychology incorporates discussions that reflect the diversity within the discipline, as well as the diversity of cultures and communities across the globe.Senior Contributing AuthorsRose M. Spielman, Formerly of Quinnipiac UniversityContributing AuthorsKathryn Dumper, Bainbridge State CollegeWilliam Jenkins, Mercer UniversityArlene Lacombe, Saint Joseph's UniversityMarilyn Lovett, Livingstone CollegeMarion Perlmutter, University of Michigan

By the end of this section, you will be able to:Describe important physical features of wave formsShow how physical properties of light waves are associated with perceptual experienceShow how physical properties of sound waves are associated with perceptual experience

Students learn about sound and sound energy as they gather evidence that sound travels in waves. Teams work through five activity stations that provide different perspectives on how sound can be seen and felt. At one station, students observe oobleck (a shear-thickening fluid made of cornstarch and water) “dance” on a speaker as it interacts with sound waves (see Figure 1). At another station, the water or grain inside a petri dish placed on a speaker moves and make patterns, giving students a visual understanding of the wave properties of sound. At another station, students use objects of various materials and shapes (such as Styrofoam, paper, cardboard, foil) to amplify or distort the sound output of a homemade speaker (made from another TeachEngineering activity). At another station, students complete practice problems, drawing waves of varying amplitude and frequency. And at another station, they experiment with string (and guitar wire and stringed instruments, if available) to investigate how string tightness influences the plucked sound generated, and relate this sound to high/low frequency. A worksheet guides them through the five stations. Some or all of the stations may be included, depending on class size, resources and available instructors/aides, and this activity is ideal for an engineering family event.

Students learn about ultrasound and how it can be used to determine the shapes and contours of unseen objects. Using a one-dimensional ultrasound imaging device (either prepared by the teacher or put together by the students) that incorporates a LEGO(TM) MINDSTORMS(TM) NXT intelligent brick and ultrasonic sensor, they measure and plot the shape of an unknown object covered by a box. Looking at the plotted data, they make inferences about the shape of the object and guess what it is. Students also learn how engineers use high-frequency waves in the design of medical imaging devices, the analysis of materials and oceanographic exploration. Pre/post quizzes, a worksheet and a LEGO rbt program are provided.