Which term means the dependence of velocity or other physical parameters on frequency?

Which term means the dependence of velocity or other physical parameters on frequency?

• A. Dispersion
• B. Energy
• C. Density
• D. Duty factor

Answer: (A)

Dispersion. In ultrasound, dispersion means the velocity of sound depends on frequency. When a medium is dispersive, different frequency components of a pulse travel at different speeds, so the pulse can broaden and its spectrum can shift as it propagates. This contrasts with non-dispersive media, where velocity is effectively the same across frequencies and the pulse maintains its shape. The other terms don’t describe this frequency-dependent behavior: energy isn’t about how velocity changes with frequency, density is mass per volume, and duty factor relates to the timing of the ultrasound pulse rather than wave speed.

Dispersion. In ultrasound, dispersion means the velocity of sound depends on frequency. When a medium is dispersive, different frequency components of a pulse travel at different speeds, so the pulse can broaden and its spectrum can shift as it propagates. This contrasts with non-dispersive media, where velocity is effectively the same across frequencies and the pulse maintains its shape. The other terms don’t describe this frequency-dependent behavior: energy isn’t about how velocity changes with frequency, density is mass per volume, and duty factor relates to the timing of the ultrasound pulse rather than wave speed.