The ultrasonic sound waves employed in ultrasound machine for medical sonography have the frequency of: (A) 2 - 20 MHz, (B) Less than 1 MHz, (C) 20-20,000 Hz, (D) Greater than 100 MHz
Answer is A. Frequency refers to a characteristic of the sound that is, the number of times that conduction paicles vibrate back and foh per second. Frequency of sound waves is usually between 1 and 20 MHz in medical sonography. Hence the best answer for this question would be A. 2-20 MHz Christensen's Physics of Diagnostic Radiology, 4/E,Pg no 347