53 What do you see observationclaimquestion 5 3

5*3 What do you see? (observation/claim/question)

5 -3 WDYT Write the question, and TRY to answer it …. remember…any THOUGHTFUL answer is ‘correct--

5*3 Notes: Revisiting Sounds in vibrating Strings Draw AND label a STANDING WAVE The length of the string = ½ OR 2×length=λ λ

1. Frequency and Wavelength • Wavelength (λ) = 2× length of string ½ λ = length of string • The higher the pitch, the __greater _ the frequency • The longer the string, the __longer_ the wavelength λ is INVERSELY related to the f (pitch)

2. Tension of a String & Frequency • An increase in tension needs a larger force • A larger force will make a greater acceleration • A greater acceleration generates a faster vibration • A faster vibration = A faster velocity Tension is DIRECTLY related to f (pitch)

3. Thickness of a String & Frequency • Thicker strings = Lower frequency and pitch • Heavier mass = smaller acceleration • Slow acceleration = slow velocity Mass is INDIRECTLY related to f (pitch)

VELOCITY OF VIBRATION AND PITCH • Wavelength, mass and tension ALL relate back to the SPEED at which an instrument’s string vibrates VELOCITY is DIRECTLY related to f (pitch)

Standing Waves Is There an Equation? ? ? • Standing Waves occur when the length of the string and wavelength have a particular relationship L = (n × λ) 2 λ = (2 × L) n n = (2 × L) λ ***n = # of antinodes in the standing wave*** (ALL instruments only have 1 antinode!!!)

SAMPLE PROB #1 • What is the length of the following standing wave, if the wavelength is 10 m?