An object vibrates with a frequency of 15 Hz. Which of the following i...
It produces sound that we cannot hear because Humans can hear sounds in the frequency range 20Hz - 20000Hz.
So, Option c is correct answer.
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An object vibrates with a frequency of 15 Hz. Which of the following i...
Explanation:
Frequency and Sound:
- Frequency refers to the number of vibrations or cycles an object completes in one second.
- Sound is a form of energy that travels through matter in the form of waves. It is produced when an object vibrates, causing the molecules in the surrounding medium to vibrate as well.
Hearing Range:
- The range of human hearing is typically between 20 Hz and 20,000 Hz.
- Sounds with frequencies below 20 Hz are called infrasound, while sounds with frequencies above 20,000 Hz are called ultrasound.
- Anything below or above this range is generally inaudible to humans.
Given Frequency:
- The object in question vibrates with a frequency of 15 Hz.
- Since this frequency is below the lower limit of human hearing (20 Hz), it falls into the infrasound range.
Answer Explanation:
- Based on the given frequency of 15 Hz, we can conclude that the object produces sound waves that are below the range of human hearing.
- Therefore, the correct answer is option c) "It produces sound which we cannot hear."
Additional Information:
- Although humans cannot hear sounds with frequencies below 20 Hz, some animals, such as elephants and whales, can perceive infrasound.
- Infrasound can also be produced by natural phenomena like earthquakes and volcanic eruptions, as well as by man-made sources such as machinery and wind turbines.
- Ultrasound, on the other hand, is commonly used in medical imaging and industrial applications.
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