Explaining Vibration-Sound Relationship Practice Test

Read about Amir. He tapped a drum three times; each time he saw the top shake fast and heard boom. When he held it still, no sound. What did Amir’s observations show?

Look at what Keisha found out. She plucked a guitar string and saw it move back and forth fast. She heard a musical sound. When she touched the string, it stopped moving and the sound stopped too. What did Keisha's observations show?