Sound waves too high in frequency to be heard by the human ear, generally above 20 kHz, are known as:
A . High-frequency sound waves
B . Microwave waves
C . Ultrasonic waves
D . Short-frequency sound waves
E . None of the above
Answer: C
Sound waves too high in frequency to be heard by the human ear, generally above 20 kHz, are known as:
A . High-frequency sound waves
B . Microwave waves
C . Ultrasonic waves
D . Short-frequency sound waves
E . None of the above
Answer: C