Exam 15: Traveling Waves and Sound

A 4.24 m long,1.27 kg rope under a tension of 475 N oscillates with a frequency of 11.2 Hz.If the oscillation amplitude is 6.32 cm,how much energy is required to keep the rope oscillating for 5.52 s?

Radar involves using an electromagnetic wave to detect an object by observing the reflected energy from that object.Assume an aircraft has a radar cross section of 710 m²,and the receiving antenna has a cross section twice as large.If the aircraft is 50 km away,what percentage of the radiated energy is eventually detected?

The density of aluminum is 2700 kg/m³.If transverse waves propagate at 34 m/s in a 4.6 mm diameter aluminum wire,what is the tension on the wire?

If a wave has a wavelength of 25.4 cm and a frequency of 1.63 kHz,its speed is closest to:

What is the intensity level in decibels of a sound whose intensity is 10^-7 W/m²?

The siren of an ambulance wails at 1395 Hz when the ambulance is stationary.What frequency will you hear after this ambulance passes you while traveling at 33.60 m/s? The speed of sound under the prevailing conditions is 343.0 m/s.

If a wave has a speed of 362 m/s and a period of 4.17 ms,its wavelength is closest to:

Crests of an ocean wave pass a pier every 12.0 s.If the waves are moving at 5.6 m/s,what is the wavelength of the ocean waves?

Suppose a water wave is moving radially outward on the surface of the water from a point source.How should the power in a small segment of the wave front depend on the radial distance from the source?

-In the figure,which of the curves best represents the variation of wave speed as a function of tension for transverse waves on a stretched string?

The intensity of sunlight impinging on Earth is about 1.4 kW/m².What is the power emitted by the Sun in the spectrum of frequencies? (Earth-Sun distance = 1.5 × 10⁸ km,Earth radius = 6.4 × 10³ km. )

For a sound wave in air of frequency 3500 Hz and average intensity 1 W/m² (pain threshold)what is the maximum change in pressure (pressure amplitude)of the wave?

A crane lifts a 2500 kg mass using a steel cable whose mass per unit length is 0.65 kg/m.What is the speed of transverse waves on this cable?

Transverse waves propagate at 43.2 m/s in a string that is subjected to a tension of 60.5 N.If the string is 15.9 m long,what is its mass?

A 2.31 kg rope is stretched between supports 10.4 m apart.If one end of the rope is tweaked,how long will it take for the resulting disturbance to reach the other end? Assume that the tension in the rope is 74.4 N.

A wave travels on a string with amplitude velocity v = 90.0 cm/s.If the tension on the string is increased by 20.0%,how much would the transmitted power on the string change if the wavelength is kept constant?

Situation 15.1 A train is approaching a signal tower at a speed of 40 m/s.The train engineer sounds the 1000 Hz whistle and a switchman in the tower responds by sounding the 1200 Hz siren.The air is still and the speed of sound is 340 m/s. -In Situation 15.1,the frequency of the train whistle tone,heard by the switchman,in SI units,is given by:

A wire,6.0 m long,with a mass of 10 g,is under tension.A transverse wave is propagated on the wire,for which the frequency is 280 Hz,the wavelength is 0.60 m,and the amplitude is 8.4 mm.The time,for a crest of the transverse wave to travel the length of the wire,in ms,is closest to:

The sound from a truck moving at 17.00 m/s reflects from a cliff and is heard by an observer on the truck.What is the change in frequency for a wave with initial wavelength γ = 0.1500 m?

The howler monkey is the loudest land animal and can be heard up to a distance of 2.5 km.Assume the acoustic output of a howler to be uniform in all directions.The acoustic power emitted by the howler,in mW,is closest to: