Cambridge Secondary (7-9). Stage 9. MCE Science. Workbook - Unit 11: Sound - Question 10

Use a 30 cm plastic ruler and a table. Place the ruler perpendicular to the table edge, with 15 cm extending over it. Hold the ruler firmly flat on the table and flick the free end. Listen to its pitch as the reference (control) test. Repeat with extensions of 5 cm, 10 cm, 20 cm and 25 cm, comparing each pitch with the 15 cm reference.



Suggest how you could improve this experiment.