A sound wave, travelling in air, approaches a solid barrier with a gap in the middle.Fig. 6.1represents the compressions and rarefactions of the sound wave. The compressions are labelledA, B and C.AcompressionbarrierrarefactionB CFig. 6.1(a) State how a compression differs from a rarefaction...................................................................................................................................................................................................................................................................................................[1](b) The speed of sound in air is 340 m / s. The frequency of the sound is 850 Hz.For this wave, determine(i) the wavelength,wavelength = ...........................................................[2](ii) the time that elapses before compression A reaches the barrier.time = ...........................................................[2](c) On Fig. 6.1, draw the shape and positions of compressions B and C as compression Areaches the barrier. [2](d) Sound waves can also travel in water.State how the speed of sound in water compares with the speed of sound in air...............................................................................................................................................

A sound wave in air consists of alternate compressions and rarefactions along its path.(i) Explain how a compression differs from a rarefaction...................................................................................................................................................................................................................................................................................[1](ii) Explain, in terms of compressions, what is meant by1. the wavelength of the sound,....................................................................................................................................................................................................................................................................[1]2. the frequency of the sound.....................................................................................................................................................................................................................................................................[1](b) At night, bats emit pulses of sound to detect obstacles and prey. The speed of sound in air is340m/s.(i) A bat emits a pulse of sound of wavelength 0.0085 m.Calculate the frequency of the sound.frequency = ...........................................................[2](ii) State why this sound cannot be heard by human beings...................................................................................................................................................................................................................................................................................[1](iii) The pulse of sound hits a stationary object and is reflected back to the bat. The pulse isreceived by the bat 0.12 s after it was emitted.Calculate the distance travelled by the pulse of sound during this time.distance = ..........................................................

A sound wave has a wavelength of 6.m. The distance from a compression centre to the adjacent rarefaction centre is :

Which of the following statements about sound waves is incorrect?Sound waves cannot travel through a vacuumSound waves are longitudinal wavesIt is not possible to measure the wavelength of a sound waveThe vibrating particles which make up a sound wave form more dense regions called compressions and less dense regions called rarefactions2Domestic cats can hear sound waves with a maximum wavelength of 6 m.  What is the frequency of a sound wave with this wavelength?  The speed of sound in air is approximately 330 m/s.55 Hz324 Hz0.018 Hz (2 s.f.)1,980 Hz3What is the function of the cochlea?It allows the ear to detect very quiet soundsIt protects the ear against infectionIt controls air pressure within the earIt converts vibrations within the ear into electrical signals4What is the range of frequencies over which the human ear can detect sound waves?From 20 Hz to 2,000 HzFrom 20 Hz to 20,000 HzFrom 20 Hz to 20,000 kHzFrom 20 Hz to 200,000 Hz

Sound is:A. a wave that propagates in an elastic medium with aspeed that depends on the medium itselfB. an elastic wave that propagates in vacuum at a speed of340 m/ sC. a wave that propagates in an elastic medium at a speedof 300 000 km/ sD. an elastic wave that propagates in vacuum at a speed of300 000 km/ sE. a wave that propagates in vacuum and all material medi-ums at a speed of 340 m/ s

If λ𝜆  is the wavelength of a wave then what will be the distance between a compression and adjacent rarefaction?