Ultrasound has frequency of vibration
$(a)$. between 20 and 20000 Hz
$(b)$. below 20 Hz
$(c)$. above 20000 Hz
$(d)$. between 500 and 10000 Hz

Academic Physics NCERT Class 8

An ultrasound wave has a frequency of vibration above $20000\ Hz$.

Therefore, option $(c)$ is correct.

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Updated on: 10-Oct-2022

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