Blog 11: Phone Physics

When I was in 4th grade, I used to play with other people's cell phones all the time. I went from playing snake or bowling to playing Mary Had a Little Lamb with the keypad numbers. This past week I realized that I could play this song or Hot Cross Buns because each key in a row had a different frequency, so some were higher than the rest. For example, 1, 4, 7, and * have the highest tones, then 2, 5, 8 and 0 and 3, 6, 9, and # have the lowest tones. Since 1, 4, 7, and * are higher in tone, they have the highest frequency, while 3, 6, 9, and # have lower frequencies. Unlike a piano where when you hold down a key, there is a consistent sound made, but when I hold down a phone key it only makes one beep. This means that the period is very short because not much time is needed to make one vibration. Also I remember on the old Nokia phones, there used to be an application where you could make your own ringtone. Each key would be a different note and you could compose a song with all the keys. In this case, every key had a different frequency.