Spatial pulse length is directly proportional to wavelength. Which statement best describes this relationship?

Spatial pulse length is directly proportional to wavelength. Which statement best describes this relationship?

• A. Directly proportional
• B. Inversely proportional
• C. Not related
• D. Only under certain conditions

Answer: (A)

Spatial pulse length tells us how long the ultrasound pulse stretches in space. It’s found by multiplying the number of cycles in the pulse by the wavelength. So when the wavelength grows, the length of each cycle grows in space, and the overall pulse length grows by the same factor. That makes the relationship direct: spatial pulse length is directly proportional to wavelength. Doubling the wavelength doubles the SPL. The other descriptions don’t fit because they imply an inverse or no relationship, or suggest the link only under special conditions, which isn’t how SPL behaves given SPL = number of cycles × λ.

Spatial pulse length tells us how long the ultrasound pulse stretches in space. It’s found by multiplying the number of cycles in the pulse by the wavelength. So when the wavelength grows, the length of each cycle grows in space, and the overall pulse length grows by the same factor. That makes the relationship direct: spatial pulse length is directly proportional to wavelength. Doubling the wavelength doubles the SPL. The other descriptions don’t fit because they imply an inverse or no relationship, or suggest the link only under special conditions, which isn’t how SPL behaves given SPL = number of cycles × λ.