Medical ultrasound imaging commonly employs sound waves of frequency 2.50 MHz that travel through soft tissue at approximately 1.54×10³ m s⁻¹.
A technician is examining a uniform section of tissue that is 4.00 cm thick (measured along the beam direction).
(a) Calculate the wavelength of the ultrasound in the tissue.
(b) Determine how many full wavelengths fit inside the 4.00 cm thickness.
(c) The transducer emits a continuous sinusoidal wave. Compute the duration required for exactly 20 successive wave crests to pass a fixed point within the tissue.
(d) If the technician switches to a probe operating at 5.00 MHz while all other conditions remain the same, explain quantitatively how the answers to parts (a)–(c) would change.