AP TET Paper 2 Math and Science Model Paper 1

Concept:Ultrasonics are sound waves having a frequency higher than the normal human hearing range.Explanation:The human ear can usually hear sounds between $20\ \mathrm{Hz}$ and $20,000\ \mathrm{Hz}$.Sound waves with frequency above $20,000\ \mathrm{Hz}$ are called ultrasonics.These high-frequency waves are used in medical imaging, cleaning, and distance measurement.Therefore, ultrasonics are sound waves with frequency greater than $20,000\ \mathrm{Hz}$.Answer:Greater than $20,000\ \mathrm{Hz}$. Option A.