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Read Spectra 9, Spectra's Sonic Surprise, and help Spectra cope with musical mayhem as her powers go on the fritz! If you would like to download the teacher's manual, including the activities, you can do that here.
Spectra and her gang are in for some big surprises this year leading up to the big Valentine's Day dance. It seems that Lucy isn't the only one to mysteriously gain powers in this town—this time Kas is in for quite the shock! Your students will learn about sound and vibrations as they follow Spectra's adventures.
If you'd like to purchase a kit for Spectra's Sonic Surprise or copies of any of our comic books, please visit our online store.
Activity 1: Straw Trombone
Answer: As the length of the vibrating object increases, the pitch drops.
Doubling the length of the resonator doubles the frequency, and lowers the pitch by an octave.
Activity 2: Talking Tape
Answer: The sound waves don't spread out as much before reaching your ear, when your ear is closer to the cup.
Activity 3: Beat Frequency
Answer: The volume changes when sound waves add together or cancel out. Pitches that are similar, but not quite the same, alternate once every second per Hz of difference between the two.
Activity 4: Laser Dance Party
Answer: Using full volume on the speaker vibrates the rubber glove the most, and having a large distance between the cup and the wall creates a large pattern.
If you weren't able to receive a kit this year you can still be part of the fun. Download the manual and create your own kit!
Download the teacher's manual for Spectra 9: Sonic Surprise
(Please note: Activity 3 in the online .pdf erroneously mentions changes in pitch, rather than volume—beat frequencies cause changes in how loud the sound is, not how high or low.)