In which of the following media is the speed of sound the greatest under normal conditions ?
Steel
Sound travels as a mechanical wave that needs a medium, and its speed depends on how tightly the particles of the medium are bonded together and how quickly they can pass on vibrations.
In solids, particles are packed very closely and held by strong intermolecular forces, so vibrations are transmitted fastest. In liquids the particles are less tightly bound, giving a lower speed, and in gases like air the particles are far apart, giving the lowest speed among the three. Sound cannot travel through vacuum at all since there are no particles to carry the vibration.
Therefore, the speed of sound is greatest in steel.
Sound waves travelling through air are classified as which type of mechanical waves?
A sound signal used for checking resonance in an air-duct system has a frequency of 850 Hz. The speed of sound in air is 340 m/s. What is the wavelength of the sound wave?
A sound pulse is sent towards a cliff and an echo is heard after 1.5 s (round trip time). If the speed of sound in air is 340 m/s, the distance of the cliff from the source is :
Ultrasonic pulse echo technique, a non-destructive ultrasonic testing, is employed for any possible flaw detection in a metallic bar of thikness 30 cm. If the arrival times of the ultrasonic pulses are 45 μs and 90 μs respectively, the distance of the flaw from one end of the steel bar at which the ultrasonic pulse initially enters the steel bar, will be: