Experiment Description

Experiment

Experiment DL09    Speed of Sound in Air

Objectives
  • Measure the speed of sound by measuring the round-trip time of an echo
  • Appreciate the capability of a computer over the traditional CRO in displaying non-periodic waveforms
  • Learn the techniques in using a computer to capture the sound waves within a short time interval
  • Study the sound waves produced during an impact
Description
In this activity, you will use a Sound Sensor to detect a pulse of sound and its echo after reflection. The time between the pulse and the echo is measured by the advanced features of the Interface.

A sharp pulse of sound is produced by hitting two wooden objects. It is sent through a long paper tube and then will be reflected by the far closed end. The sensor records both the transmitted and reflected pulses. The Scope display is set so that when one complete trace is formed, the sensor stops recording. By careful analysis on the trace, the round-trip time of the echo can be measured.
Apparatus
Science Workshop 500/700/750 Interface [1]
Sound Sensor [1]
cardboard tube (diameter 15 cm, length 1.5 m) [1]
wooden block [1]
wooden hammer [1]
Experiment