If frequency increases from 1 MHz to 2 MHz in soft tissue while speed remains constant, what happens to the wavelength?

If frequency increases from 1 MHz to 2 MHz in soft tissue while speed remains constant, what happens to the wavelength?

• A. Increases
• B. Doubles
• C. Decreases by half
• D. Stays the same

Answer: (C)

Wavelength scales inversely with frequency when the propagation speed is fixed. The relationship is v = f·λ, so λ = v / f. If the frequency doubles while speed stays the same, the wavelength becomes half as big. For soft tissue, using about 1540 m/s, the wavelength goes from roughly 1.54 mm at 1 MHz to about 0.77 mm at 2 MHz. So the wavelength decreases by half.

Wavelength scales inversely with frequency when the propagation speed is fixed. The relationship is v = f·λ, so λ = v / f. If the frequency doubles while speed stays the same, the wavelength becomes half as big. For soft tissue, using about 1540 m/s, the wavelength goes from roughly 1.54 mm at 1 MHz to about 0.77 mm at 2 MHz. So the wavelength decreases by half.