![]() The threshold for pain is about 130 dB, a jet plane taking off or a revolver firing at close range (Dunkle, 1982).Quality AssuranceOne of the foremost manufacturers and suppliers of high quality dyes and intermediates in the dyestuff industry. However, there is the potential for hearing damage from about 80 dB to 130 dB: These are sounds of a food processor, power lawnmower, heavy truck (25 feet away), subway train (20 feet away), live rock music, and a jackhammer. A whisper 5 feet away or rustling leaves are at the low end of our hearing range sounds like a window air conditioner, a normal conversation, and even heavy traffic or a vacuum cleaner are within a tolerable range. A typical conversation would correlate with 60 dB a rock concert might check in at 120 dB ( ). Loudness is measured in terms of decibels (dB), a logarithmic unit of sound intensity. Higher amplitudes are associated with louder sounds. The loudness of a given sound is closely associated with the amplitude of the sound wave. ![]() Our pet dogs and cats have audible ranges of about 70–45000 Hz and 45–64000 Hz, respectively (Strain, 2003). Mice have an audible range from 1000 to 91000 Hz, and the beluga whale’s audible range is from 1000 to 123000 Hz. For instance, chickens have a very limited audible range, from 125 to 2000 Hz. The audible range of sound frequencies is between 0 Hz, with greatest sensitivity to those frequencies that fall in the middle of this range.Īs was the case with the visible spectrum, other species show differences in their audible ranges. High-frequency sound waves are perceived as high-pitched sounds, while low-frequency sound waves are perceived as low-pitched sounds. The frequency of a sound wave is associated with our perception of that sound’s pitch. Like light waves, the physical properties of sound waves are associated with various aspects of our perception of sound. (credit: modification of work by Johannes Ahlmann) SOUND WAVES For instance, honeybees can see light in the ultraviolet range (Wakakuwa, Stavenga, & Arikawa, 2007), and some snakes can detect infrared radiation in addition to more traditional visual light cues (Chen, Deng, Brauth, Ding, & Tang, 2012 Hartline, Kass, & Loop, 1978).ĭifferent wavelengths of light are associated with our perception of different colors. Other species can detect other portions of the electromagnetic spectrum. The visible spectrum in humans is associated with wavelengths that range from 380 to 740 nm-a very small distance, since a nanometer (nm) is one billionth of a meter. As shows, the electromagnetic spectrum encompasses all of the electromagnetic radiation that occurs in our environment and includes gamma rays, x-rays, ultraviolet light, visible light, infrared light, microwaves, and radio waves. The visible spectrum is the portion of the larger electromagnetic spectrum that we can see. Moving from top to bottom, the wavelengths decrease and frequencies increase. At the top of the figure, the red wave has a long wavelength/short frequency. This figure illustrates waves of differing wavelengths/frequencies.
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