To calculate the time, use the formula time = distance / speed. Convert the distance from kilometers to meters: 7 km = 7000 meters. Dividing 7000 m by 700 m/s yields 10 seconds. This calculation assumes a constant speed of sound throughout the medium.
15462
What is the frequency range to which the human ear exhibits the highest sensitivity?
The human ear is physiologically most sensitive to sounds in the 2000 to 4000 Hz range. This sensitivity is largely due to the resonance characteristics of the human ear canal, which amplifies these specific frequencies, facilitating the perception of speech and other critical environmental sounds.
15463
Through which of the following media is the transmission of sound waves impossible?
Sound is a mechanical wave that requires a material medium (solid, liquid, or gas) to propagate through the vibration of particles. In a vacuum, there are no particles to transmit these vibrations, therefore sound cannot travel.
15464
In which medium is the speed of sound at its maximum?
The speed of sound is highest in solids because the atoms are tightly bound together, allowing the mechanical disturbance to propagate more rapidly than in liquids or gases. In a vacuum, sound cannot travel at all because there is no material medium to support the wave propagation.
15465
What is the fundamental cause of the production of sound waves?
Sound waves are mechanical waves generated by the vibration of an object. When a body vibrates, it causes the surrounding medium (such as air) to compress and rarefy, creating pressure disturbances that propagate outward as sound. Without the initial vibration of a source, such as a guitar string or vocal cords, there would be no mechanical energy to initiate the wave motion in the medium.
15466
Among the following materials, in which does sound travel the fastest?
Sound speed is determined by the density and elastic properties of the medium. Steel, being a solid with high elasticity, allows sound waves to travel significantly faster (approximately 5000 m/s) than in liquids like water (1500 m/s) or gases like air (340 m/s). Sound cannot travel in a vacuum.
15467
In which year was the speed of sound in air first determined with significant accuracy?
The first accurate measurement of the speed of sound in air is historically attributed to the French Academy of Sciences in 1738. A team led by Cassini de Thury conducted experiments using cannon fire at a known distance, timing the interval between the flash and the sound to calculate the velocity of sound waves.
15468
Calculate the velocity of a sound wave that has a wavelength of 2.5 m and a frequency of 400 Hz.
The velocity (v) of a wave is calculated using the formula v = f × λ, where f is frequency and λ is wavelength. Given f = 400 Hz and λ = 2.5 m, the calculation is 400 × 2.5 = 1000 m/s. This represents the speed at which the wave phase propagates through the medium.
15469
What is the term used to describe sound waves with a frequency lower than 20 Hz?
Sound waves are categorized by their frequency range. Frequencies below the human hearing threshold of 20 Hz are classified as infrasonic. Frequencies above 20,000 Hz are classified as ultrasonic, while the range between 20 Hz and 20,000 Hz is considered audible sound.
15470
What physical phenomenon is responsible for the creation of an echo?
An echo occurs when sound waves encounter a surface and bounce back to the listener. This reflection of sound waves requires a sufficient distance between the source and the reflecting surface to allow the reflected sound to be distinguished from the original sound.
