ERIC Number: EJ913077
Record Type: Journal
Publication Date: 2011-Jan
Abstractor: As Provided
Reference Count: 11
Using the Sound Card as a Timer
Aguiar, C. E.; Pereira, M. M.
Physics Teacher, v49 n1 p33-35 Jan 2011
Experiments in mechanics often involve measuring time intervals much smaller than one second, a task that is hard to perform with handheld stopwatches. This is one of the reasons why photogate timers are so popular in school labs. There is an interesting alternative to stopwatches and photogates, easily available if one has access to a personal computer with sound-recording capability. The idea is simple: a computer sound card can record audio frequencies up to several kilohertz, which means it has a time resolution of a fraction of a millisecond, comparable to that of photogate timers. Many experiments in mechanics can be timed by the sound they produce, and in these situations a direct audio recording may provide accurate measurements of the time intervals of interest. This idea has already been explored in a few cases, and here we apply it to an experiment that our students found very enjoyable: measuring the speed of soccer balls they kicked.
Descriptors: Intervals, Physics, Motion, Science Instruction, Science Experiments, Laboratory Equipment, Computer Uses in Education, Acoustics, Scientific Principles
American Association of Physics Teachers. One Physics Ellipse, College Park, MD 20740. Tel: 301-209-3300; Fax: 301-209-0845; e-mail: firstname.lastname@example.org; Web site: http://scitation.aip.org/tpt
Publication Type: Journal Articles; Reports - Descriptive
Education Level: N/A
Authoring Institution: N/A