How many times a minute does a boat bob up and down on ocean waves that have a wavelength of 40.0 m and a propagation speed of 5.00 m/s?

A cable with a linear density of =0.2 kg/m is hung from telephone poles. The tension in the cable is 500.00 N. The distance between poles is 20 meters. The wind blows across the line, causing the cable resonate. A standing waves pattern is produced that has 4.5 wavelengths between the two poles. The air temperature is T=20C . What are the frequency and wavelength of the hum?

Porpoises emit sound waves that they use for navigation. If the wavelength of the sound wave emitted is 4.5 cm, and the speed of sound in the water is v=1530 m/s, what is the period of the sound?

(I) What is the sound level of a sound whose intensity is 1.5 x 10–6 W/m2 ?

(a) Ear trumpets were never very common, but they did aid people with hearing losses by gathering sound over a large area and concentrating it on the smaller area of the eardrum. What decibel increase does an ear trumpet produce if its sound gathering area is 900 cm2 and the area of theeardrum is 0.500 cm2 , but the trumpet only has an efficiency of 5.00% in transmitting the sound to the eardrum?(b) Comment on the usefulness of the decibel increase found in part (a).

(a) An experimenter wishes to generate in air a sound wave that has a displacement amplitude of 6.20   10-6 m. The pressure amplitude is to be limited to0.850 Pa. What is the minimum wavelength the sound wave can have? (Take the equilibrium density of air to be ρ = 1.20 kg/m3 and assume the speed of sound in air is v = 343 m/s.)   (b) Calculate the pressure amplitude of a 2.80 kHz sound wave in air, assuming that the displacement amplitude is equal to 2.00 ✕ 10-8 m.[Note: Use the following values, as needed. The equilibrium density of air is ρ = 1.20 kg/m3. The speed of sound in air is v = 343 m/s. Pressure variations ΔP are measured relative to atmospheric pressure, 1.013 ✕ 105 Pa.]   (c) Earthquakes at fault lines in Earth's crust create seismic waves, which are longitudinal (P-waves) or transverse (S-waves). The P-waves have a speed of about 9 km/s. Estimate the average bulk modulus of Earth's crust given that the density of rock is about 2500 kg/m3.

(II) A fireworks shell explodes 100 m above the ground, cre- ating colorful sparks. How much greater is the sound level of the explosion for a person at a point directly below the explosion than for a person a horizontal 100 m distance of 200 m away (Fig. 12–34)? 200 m FIGURE 12-34 Problem 16.

(II) If the amplitude of a sound wave is made 3.5 times greater, (a) by what factor will the intensity increase? (b) By how many dB will the sound level increase?

(I) A sound wave in air has a frequency of 282 Hz and travels with a speed of 343m/s. How far apart are the wave crests (compressions)?