What is the reasoning for riding the Trans-siberian railroad?

Can you answer my questions? ASAP? it's kundt's TUBE: DETERMINING THE WAVELENGTH OF SOUND?

• 1. When sound travels from air into water, does the frequency of the wave change? The speed? The Wavelength? Explain your reasoning. 2. Two vibrating tuning forks have identical frequencies, but one is stationary and the other is mounted at the rim of a rotating platform. What does a listener hear? Explain. 3. Symphonic musicians always “warm up” their wind instruments by blowing into them before a performance. What purpose does this serve? 4. In a popular and amusing science demonstration, a person inhales helium and then his voice becomes high and squeaky. Why does this happen? 5. A large church has part of the organ in the front of the church and part in the back. A person walking rapidly down the aisle while both segments are playing at once reports that the two segments sound out of tune. Why? 6. A railroad train is travelling at 25.0 m/s in still air. The frequency of the note emitted by the locomotive whistle is 400 Hz. What is the wavelength of the sound waves a) in front of the locomotive and (b) behind the locomotive? What is the frequency of the sound heard by a stationary listener c) in front of the locomotive and (d) behind the locomotive? 7. A sound source and a listener are both at rest on the earth, but a strong wind is blowing front the source toward the listener. Is there a Doppler Effect? Why or why not? 8. Does an aircraft make a sonic boom only at the instant its speed exceeds Mach I? Explain your reasoning. 9. If you are riding in a supersonic aircraft, what do you hear? Explain your reasoning. In Particular, do you hear a continuous sonic boom? Why or Why not? 10. What conclusions can you draw from this experiment?

• Answer:

  The tube is a transparent horizontal pipe which contains a small amount of a fine powder such as cork dust, talc or Lycopodium.[3] At one end of the tube is a source of sound at a single frequency (a pure tone). Kundt used a metal rod resonator that he caused to vibrate or 'ring' by rubbing it, but modern demonstrations usually use a loudspeaker attached to a signal generator producing a sine wave. The other end of the tube is blocked by a moveable piston which can be used to adjust the length of the tube. The sound generator is turned on and the piston is adjusted until the sound from the tube suddenly gets much louder. This indicates that the tube is at resonance, this means its length is a multiple of the wavelength of the sound wave. At this point the sound waves in the tube are in the form of standing waves, and the amplitude of vibrations of air are zero at equally spaced intervals along the tube, called the nodes. The powder is caught up in the moving air and settles in little piles or lines at these nodes, because the air is still and quiet there. The distance between the piles is one half wavelength λ/2 of the sound. By measuring the distance between the piles, the wavelength λ of the sound in air can be found. If the frequency f of the sound is known, multiplying it by the wavelength gives the speed of sound c in air: