What are infrasonic and ultrasonic sounds? Name the sources of infrasonic sound in nature. Describe the characteristics and applications of ultrasonic sound.

by

Points to Remember:

  • Infrasonic sounds are below the range of human hearing.
  • Ultrasonic sounds are above the range of human hearing.
  • Both have natural and artificial sources.
  • Ultrasonic sounds have specific characteristics and numerous applications.

Introduction:

Sound is a form of energy that travels as waves, caused by vibrations. The human ear can typically detect sounds within a frequency range of 20 Hz to 20,000 Hz (Hertz, or cycles per second). Sounds below 20 Hz are called infrasonic, and those above 20,000 Hz are called ultrasonic. Both are prevalent in nature and have found significant applications in various fields due to their unique properties.

Body:

1. Infrasonic Sounds:

Infrasonic sounds are characterized by their low frequency and long wavelengths. Humans cannot hear them, but many animals, such as elephants and whales, can perceive and utilize these sounds for communication over long distances.

  • Sources in Nature:
    • Natural Phenomena: Earthquakes, volcanic eruptions, avalanches, meteor impacts, and ocean waves generate infrasound. The powerful forces involved create low-frequency vibrations that propagate through the air and ground.
    • Biological Sources: Certain animals, like elephants, use infrasound for communication. Their calls travel for kilometers, allowing them to maintain contact across vast distances. Some species of whales also produce infrasonic vocalizations.
    • Atmospheric Phenomena: Strong winds, thunderstorms, and even auroras can produce infrasonic waves.

2. Ultrasonic Sounds:

Ultrasonic sounds are characterized by their high frequency and short wavelengths. Their high frequency allows them to carry more information and penetrate certain materials more effectively than audible sound.

  • Characteristics:

    • High Frequency: Frequencies range from 20 kHz to several gigahertz.
    • Short Wavelength: This allows for precise focusing and better resolution in imaging applications.
    • Directional Propagation: Ultrasonic waves tend to travel in a more focused beam than audible sound.
    • Absorption and Reflection: The extent to which ultrasonic waves are absorbed or reflected depends on the material they encounter. This property is exploited in various applications.

  • Applications:

    • Medical Imaging: Ultrasound is widely used in medical diagnosis for imaging internal organs and tissues (e.g., sonography). It’s a non-invasive and relatively safe technique.
    • Industrial Applications: Ultrasonic testing (UT) is used to detect flaws in materials like metals and welds. Ultrasonic cleaning is used to remove contaminants from delicate objects.
    • Sonar: Sonar systems use ultrasonic waves to detect objects underwater, crucial for navigation, fishing, and military applications.
    • Animal Repellents: High-frequency ultrasonic devices are used to deter pests like rodents and insects.

Conclusion:

Infrasonic and ultrasonic sounds, while imperceptible to the human ear, play significant roles in both natural processes and technological applications. Infrasound, generated by powerful natural events and animal communication, provides insights into geophysical phenomena and animal behavior. Ultrasound, with its unique characteristics, has revolutionized medical imaging, industrial inspection, and various other fields. Further research into both infrasound and ultrasound could lead to advancements in areas such as early earthquake detection, improved medical diagnostics, and more efficient industrial processes. A balanced approach, considering both the potential benefits and any potential risks associated with the use of these sound frequencies, is crucial for responsible technological development and environmental stewardship. This holistic approach ensures sustainable progress and aligns with the principles of responsible innovation.

JPSC Notes brings Prelims and Mains programs for JPSC Prelims and JPSC Mains Exam preparation. Various Programs initiated by JPSC Notes are as follows:- For any doubt, Just leave us a Chat or Fill us a querry––