1. DO NOW 1.In an open tube resonator, there is a pressure ________ at both ends. 2.In a close tube resonator, there is a pressure _________ at the closed end and a pressure ________ at the open end. node anti-node ***Note that this is the opposite of standing wave formations which represent air displacement.

2. DO NOW 1.The diagram above depicts the standing wave pattern of the fundamental frequency or __________ harmonic of a _________ tube resonator. 2.The wavelength is equal to _________ times the length of the tube. L first closed four

3. DRAWING STANDING WAVES The basis for drawing the standing wave patterns for air columns is that vibrational anti-nodes will be present at any open end and vibrational nodes will be present at any closed end. For a tube closed at one end… = nodes = anti-nodes In general, for the n th harmonic of a closed tube… Where n = 1,3,5…(odd)

4. DRAWING STANDING WAVES The basis for drawing the standing wave patterns for air columns is that vibrational anti-nodes will be present at any open end and vibrational nodes will be present at any closed end. For a tube open at both ends… = nodes = anti-nodes In general, for an n th harmonic of an open tube… Where n = 1,2,3,4… (all integers)

5. DO NOW Take out your homework… For a closed pipe… 1.The first harmonic has __________ of a wavelength 2.The third harmonic has __________ of a wavelength 3.The fifth harmonic has _________ of a wavelength 4.The seventh harmonic has _________ of a wavelength 5.The nineth harmonic has __________ of a wavelength. 1/4 3/4 5/4 7/4 9/4

6. REVIEW One person reads the question on the green side of the card ("who has: material a wave travels through"?), The answer is on the purple side of someone else's card and they respond ("I have: medium")

7. DO NOW Take out a writing utensil, your notecard (if you have it), and a calculator. Answer the following question on your DO NOW… 1.What grade do you expect to get on the practice test today? 2.What grade to you want to get on the test on Monday?

8. 1.Medium 2.Mechanical 3.Transverse 4.Longitudinal 5.Interface 6.Period 7.Electromagnetic 8.Frequency; Hertz 9.Reflection, refraction, or diffraction 10.Diffraction 11.Ray 12.Wavelength; λ 13.Electromagnetic 14.Speed 15.Source 16.Superposition or Interference 17.Nodes 18.Incident 19.C 20.C 21.B 22.B 23.A 24.C 25.B 26.D 27.C 28.C 29.D 30.B 31.A 32.C 33.C 34.D 35.D 36.C 37.D 38.1.35 m 39.880 Hz;.0011 s 40.1500m/s; 480 m 41.60 Hz; 1.50 m Yes; No 42.1.24 m; 353.4 m/s;.62 m, 570 Hz;.41 m, 855 Hz 43. 2.74 m; 125 Hz;.91 m, 375 Hz;.55 m, 625 Hz 44. 1160 Hz ; 866 Hz