Parts III and IV Speed of Sound: Resonance Method & Echo Method 5. A student is
ID: 2305995 • Letter: P
Question
Parts III and IV Speed of Sound: Resonance Method & Echo Method 5. A student is using the resonance apparatus with an unmarked tuning fork. a) If the student measures the distance between two successive resonances to be 47.2 cm, what is the wavelength of the wave? b) If the students measure the temperature in the lalb to be 21.8 oC, calculate expected speed of sound at this temperature. c) From these results calculate the frequency of the unmarked tuning fork. 6. A student is using the echo method with the microphone at the open end of an 80-cm tube that is closed at the other end. a) The student measures a time interval 0.0231 s for 5 echoes. What will the student calculate for the speed of sound? b) Based on this result, what is the temperature in the room? 7. The audible range of human hearing is roughly from about 20 Hz to 20000 Hz. Calculate the wavelengths of sound waves at these two frequencies. (Assume T 25.0 °c.) 182Explanation / Answer
7) wavaelngth = velocity of light / frequency
= c/f
= 3*10^8 / 20
= 1.5*10 ^7 m
for the higher range
= 3*10^8 / 20000 = 1.5*10^4 m