Physics
Grade-8
Easy
Question
The sounds with frequencies greater than 20 kHz are called _____.
- Ultra sound
- Infra sound
- Super sound
- Supersonic sound
Hint:
Ultrasound
The correct answer is: Ultra sound
- The sound with frequencies greater than 20KHz is called ultrasound.
- Ultrasound cannot be perceived by average human ear but some animals can perceive ultrasounds.
- So, the correct option is a.
- The audible frequency range is 20Hz to 20KHz.
- The sound with frequencies less than 20Hz is called infrasound.
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