Mini-Quiz: Creating Sound Waves

1. How does a loudspeaker create sound?

   The speaker cone vibrates back-and-forth, creating compression waves in the airThat is correct. You are becoming a <i>Champion in Physics</i>. The electricity that powers the speaker makes sounds when it cracklesSorry, not correct. Try another button. Loudspeakers don't create sound; they detect soundGood try, but not right. Select another answer.

2. How do you make sounds from your vocal chords?

   Vocal chords act like tiny loudspeakers, vibrating and forcing sound out your mouthOops! Wrong answer. Re-read the question and try again. Air from your lungs passes over the vibrating vocal chords, making soundCorrect. You are getting smarter every day! It is a myth that your sound comes from vocal chords; it comes from your chestSorry, not correct. Try another button.

3. What happens when you blow across the top of a bottle?

   The top of the bottle gets cold, making a squeaking soundOops! Wrong answer. Re-read the question and try again. Air starts to circulate and vibrate in the bottle, making a soundThat is correct. You are becoming a <i>Champion in Physics</i>. You must blow into the bottle for anything to happenGood try, but not right. Select another answer.

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