When solving a problem you would only use 2 of the

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When solving a problem, you would only use 2 of the ratios at a time. Wave speed f v Wave speed = frequency wavelength True for any wave. Speed of sound in air T v C s m s m sound / 6 . 0 331 Speed of sound = 331 + 0.6 air temperature Temperature must be in ºC. Echolocation t v D 2 1 Distance to object = ½ wave speed elapsed time The ½ is there because the waves travel from the source to the object and then bounce off of the object & return to the source. Wavelength n L Wavelength = total length / number of waves True for any wave. Frequency t n f Frequency = number of waves / elapsed time True for any wave. Period n t T Period = elapsed time / number of waves True for any wave. Optic formula i o d d f 1 1 1 f is focal length d o is object distance d i is image distance Object distance is always positive. This formula applies to both lenses & mirrors. Theoretical magnification o i d d M Theoretical magnification = negative image distance / object distance Object distance & height are always positive. For the HW, assume the theoretical magnification & the actual magnification equal each other. In lab, they will most likely not equal each other due to measurement errors for the distances & heights. Measured magnification o i h h M Measured magnification = image height / object height
Appendix
Review for Graph Final Use the graph below to answer the following questions. 1. When does the moped have positive position? 2. When does the moped have negative position? 3. When is the moped at rest? 4. When is the moped moving with positive velocity? 5. When is the moped moving with negative velocity? 6. What is the moped’s velocity at t = 5 h? 7. What is the moped’s velocity at t = 7.5 h? 8. What is the moped’s velocity at t = 9 h? 9. What is the total distance covered by the moped? 10. What is the total displacement of the moped? Use the graph below to answer the following questions. 11. When does the car’s velocity equal zero? 12. When is the car’s velocity positive? 13. When is the car ’s velocity negative? 14. What is the car’s acceleration at t=1 s? 15. What is the car’s acceleration at t=2.5 s? 16. What is the car’s acceleration at t=4 s? 17. What is the car’s acceleration at t=6.5 s? 18. What is the car’s acceleration at t=9 s? 19. When is the car speeding up? 20. When is the car slowing down? 21. What is the maximum speed of the car? 22. When does the car have constant velocity? -40 -20 0 20 40 0 2 4 6 8 10 Position (mi) Time (h) Moped Position vs. Time -4 -2 0 2 4 0 2 4 6 8 10 Velocity (m/s) Time (s) Car Velocity vs. Time
Read the following paragraph and then use the graph to answer the following questions. A mysterious substance is cooled for 90 minutes. During that time the substance went from gas to liquid to solid. 23. Why is the temperature of the substance not changing at t = 60 min? 24. At what temperature did freezing occur?
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