The goal of this activity is for students to devise an experiment that allows them to determine the speed of sound through air.

In the Preliminary Observations, students will observe sound waves that are “delayed” in their arrival, such as seeing a gun flash before hearing it. Students will then estimate how fast sound waves travel through air and devise a method for measuring it. Since groups may choose different methods, you will need to have a class discussion after the investigations to summarize the class’s findings.


  • Design and perform an investigation.
  • Draw a conclusion from evidence.
  • Estimate the speed of sound.
  • Experience measuring a quantity that does not fit into previous experimental models and requires a novel approach.