Other sudents like me, dante, is always greatfull for what she did, along with caroline and dessirey.
Check out our National Walk to School Day at Hill, featured on today's news!
http://www.fox7austin.com/news/local-news/209746522-story Sound is produced by vibrations!
When something vibrates, it makes the particles in the air vibrate, which travel to your ear and make your ear drum vibrates. Then tiny bones in your ear vibrate and travel to a nerve which sends a message to your brain that you heard sound. Pitch refers to how high or low the sound of the note is. Pitch is determined by length of string. A short string vibrates quickly, has a high frequency. That produces a high pitch. A long string vibrates slowly, a lower frequency. That produces a lower pitch. People who have long vocal cords have lower voices. People who have shorter vocal cords have higher voices. Pitch is measured in Hertz. 260 Hertz means that the string is vibrating 260 times per second. Middle C has a pitch of 261.6 Hz. Humans can hear 20-20,000 Hertz. Animals have different pitch ranges. For example, dogs can hear from 40 hz to 60,000 Hz (so they can hear much higher pitches than us.) Loudness is measured by decibels. A whisper is about 15 decibels and a Jet engine is about 150 decibels. The human pain threshold is about 130 decibels. Always be careful when listening to music, never play it too loud! A sound board amplifies sound. Instruments such as the piano, guitar, harp and violin have sound boards. The string vibrates against the soundboard, making it vibrate at the exact same frequency as the string, just louder. The string would still make sound without a soundboard, but it would be much quieter. The greater the surface area of the sound board, moves greater volume of air, with produces a louder sound. Soundboards are usually made of wood. Harp Facts: Harps have a soundboard, strings, pedals, and a column. The average pedal harp is 80 pounds and 6 feet. Harps have been around for centuries, dating back to stone ages, and the use of lyres. There are 1,000+ moving parts in a pedal harp. Most pedal harps have 47 stings. A lever harp is a smaller harp, without pedals. Visit Mrs. Cotten's Harp Website for videos and pictures! The Mock Elections start at 5:00 and going until 7:00 for the live results!!! Channel 22 or the link below:
AISD LIVE Great job voting today! You did your civic duty! Now check out the results tonight! |
AuthorEvery two weeks we have 2 student website managers and 2 student photojournalists who blog and report about what we are learning in class. Mrs. Cotten also helps out with the blogging, but most is completed by the students. Archives
August 2017
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