1. Monday Back to waves IB Physics

2. Hand back and go over test Chance to earn points back on Wed. block lunch- here – multiple choice – poss. 10 points!!!!!!!!!!!!!

3. Back to waves Ch. 16 + 17 HW questions will be posted today Discuss lab – waves 1 ppt. slide 6 v = λf so λ = v/f From wave math relationship (slide6) L = (n/2)(λ) sub in L = (n/2)(v/f) so f = nv/2L - shows relationship between f and mode #!!!!

4. Closed tube? Like in lab 1 st mode = ¼ λ L = ¼ λ L = ¾ λ L = 5/4 λ antinode 1 st harmonic (overtone) 2 nd harmonic 3 rd harmonic

5. Odd series of #s math relationship 2n – 1 L = (2n – 1) /4 λ λ = v/f So L = (2n – 1) / 4 v/f

6. Open tube Anti-node on both ends

7. Wave on a string demo Reflection and standing waves pHET

8. Superposition - ex waves moving toward each other – cancel – then continue… Velocity – of string – v = F t / (m/L) Resonance – E at correct moment - Amp Tacoma bridge collapse Diffraction – waves bend around corners… Interference – constructive/destructive waves ppt. slides 8 and 9

9. One last thing: Refraction info. Sinθ i V i λ i n r Sinθ r = v r = λ r = n i