3267General KnowledgeMedium
Ultrasonic waves are those sound waves having frequency __________?
Abetween 20 hertz and 1000 hertz
Bmore than 20 kilohertz
Cbetween 1000 hertz and 20000 hertz
Dless than 20 hertz
Correct answer
B. more than 20 kilohertz
Explanation
more than 20 kilohertz is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.