HCI 08 Oscillations Lecture Notes

Hwa Chong Institution (College) H2 Physics C1 2023 1 Chapter 8 Oscillations A metronome, which is basically an upside down pendulum, is a device that produces regular ticks (beats). It dates back to the early 19th century. A metronome is used by some performing musicians for practice in maintaining a consistent tempo; it gives the composer an approximate way of specifying the tempo. From its inception, however, the metronome has been a highly controversial tool, and there are musicians who reject its use altogether. - http://en.wikipedia.org/wiki/Metronome

Hwa Chong Institution (College) H2 Physics C1 2023 2 Oscillations Candidates should be able to: (a) describe simple examples of free oscillations. (b) investigate the motion of an oscillator, using experimental and graphical methods. (c) show an understanding of and use the terms amplitude, period, frequency, angular frequency and phase difference and express the period in terms of both frequency and angular frequency. (d) recall and use the equation 2ax  as the defining equation of simple harmonic motion. (e) recognise and use 0 sinx x t  as a solution to the equation 2ax  . (f) recognise and use the equations 0 cosv v t  and 22 0v x x   . (g) describe, with graphical illustrations, the changes in displacement, velocity and acceleration during simple harmonic motion. (h) describe the interchange between kinetic energy and potential energy during simple harmonic motion. (i) describe practical examples of damped oscillations with particular reference to the effects of the degree of damping and to the importance of critical damping in applications such as a car suspension system. (j) describe practical examples of forced oscillations and resonance. (k) describe graphically how the amplitude of a forced oscillation changes with driving frequency near to the natural frequency of the system, and understand qualitatively the factors which determine the frequency response and sharpness of the resonance. (l) show an appreciation that there are some circumstances in which resonance is us eful and other circumstances in which resonance should be avoided. RELEVANT E-LEARNING WEBSITES Applets 1) Spring-Mass SHM http://ngsir.netfirms.com/j/Eng/springSHM/springSHM_js.htm 2) Mass Spring Lab https://phet.colorado.edu/en/simulation/mass-spring-lab Online lessons 3) University of Salford Online Lessons: http://www.acoustics.salford.ac.uk/feschools/waves/shm.htm#motion 4) PHYSCLIP Online Lessons a. Mechanics: SHM (http://www.animations.physics.unsw.edu.au/mechanics/chapter4_simpleharmonicmotion.html) b. Waves and Sound: Oscillations (http://www.animations.physics.unsw.edu.au/waves-sound/oscillations/) 5) Schoolphysics: http://www.schoolphysics.co.uk/age16-19/Mechanics/Simple%20harmonic%20motion/ 6) How Radio works http://electronics.howstuffworks.com/radio8.htm

Hwa Chong Institution (College) H2 P