Home
/
Physics
/
8. How Do Longitudinal Waves Differ from Transverse Waves?Use a Diagram and Have Example for Each. 9. A Plane Flies at Mach2.2. How

Question

8. How do longitudinal waves differ from transverse waves?Use a diagram and have example for each. 9. A plane flies at Mach2.2. How long does it take to fly across the Atlantic Ocean which is approximate 8.0times 10^3km across. (air temp=0^circ C) [3.1hrs] 10. A standing wave is produced on a 1.0 m spring with 5 nodes (including fixed ends). a. How many antinodes are there? [4] If the frequency of the source is 5.0Hz, what is the speed of the wave? [2.5m/s] 11. In a closed air column, a tuning fork of frequency 128Hz is struck and the temperature is 22^circ C a. Determine the first resonant length of the air column. [0.67m]

Solution

Expert Verified
4 (236 Votes)
Joel Master · Tutor for 5 years

Answer

**8. Longitudinal vs. Transverse Waves:*** **Transverse Waves:** In transverse waves, the particle displacement is *perpendicular* to the direction of wave propagation. Think of shaking a rope up and down – the wave travels along the rope, but the particles of the rope move up and down. * **Diagram:** ``` Wave propagation --> /\ /\ /\ / \ / \ / \ / \ / \ / \ _/______\/______\/______\ Particle displacement ``` * **Example:** Light waves, waves on a string, seismic S-waves.* **Longitudinal Waves:** In longitudinal waves, the particle displacement is *parallel* to the direction of wave propagation. Think of a sound wave – the air particles compress and expand along the direction the sound travels. * **Diagram:** ``` Wave propagation --> | ||| | ||| | ||| | | ||| | ||| | ||| | | ||| | ||| | ||| | Compression/Rarefaction ``` * **Example:** Sound waves, seismic P-waves.**9. Supersonic Flight Time:*** **Mach Number:** Mach number is the ratio of the object's speed to the speed of sound. Mach 2.2 means the plane is traveling at 2.2 times the speed of sound.* **Speed of Sound:** The speed of sound in air at 0°C is approximately 331 m/s.* **Plane's Speed:** Speed = Mach number * Speed of sound = 2.2 * 331 m/s = 728.2 m/s* **Distance:** 8.0 x 10³ km = 8.0 x 10⁶ m* **Time:** Time = Distance / Speed = (8.0 x 10⁶ m) / (728.2 m/s) = 11013.45 s ≈ 3.06 hours (approximately 3.1 hours)**10. Standing Waves on a Spring:*** **a) Antinodes:** A standing wave with 5 nodes (including the fixed ends) will have 4 antinodes. The number of antinodes is always one less than the number of nodes.* **b) Wave Speed:** * **Wavelength:** With 5 nodes on a 1.0 m spring, there are 2 full wavelengths. Therefore, the wavelength (λ) is 1.0 m / 2 = 0.5 m. * **Speed:** Wave speed (v) is given by the formula v = fλ, where f is the frequency. v = (5.0 Hz)(0.5 m) = 2.5 m/s**11. Resonant Length of Air Column:*** **Wavelength:** For the first resonance in a closed air column, the length of the air column is one-quarter of the wavelength (λ/4).* **Speed of Sound at 22°C:** The speed of sound in air increases with temperature. We can use the approximation v = 331 m/s + (0.6 m/s/°C) * T, where T is the temperature in Celsius. v = 331 m/s + (0.6 m/s/°C) * 22°C ≈ 344.2 m/s* **Wavelength:** v = fλ => λ = v/f = (344.2 m/s) / (128 Hz) ≈ 2.69 m* **Resonant Length:** Length = λ/4 = (2.69 m) / 4 ≈ 0.67 m