Which unit is used to express pressure amplitude in clinical imaging?

Which unit is used to express pressure amplitude in clinical imaging?

• A. Joules
• B. Newtons
• C. Pascals
• D. Watts

Answer: (C)

Pressure amplitude refers to how large the pressure fluctuations are in tissue when an ultrasound wave passes. Pressure is defined as force per area, and its SI unit is the pascal (N/m^2). That makes pascals the natural unit for expressing pressure amplitude. Other options—joules (energy), newtons (force), and watts (power)—describe different physical quantities and don’t quantify pressure itself. In practice, you’ll see values given in kilopascals or megapascals, but they’re still expressed in pascals with a prefix.

Pressure amplitude refers to how large the pressure fluctuations are in tissue when an ultrasound wave passes. Pressure is defined as force per area, and its SI unit is the pascal (N/m^2). That makes pascals the natural unit for expressing pressure amplitude. Other options—joules (energy), newtons (force), and watts (power)—describe different physical quantities and don’t quantify pressure itself. In practice, you’ll see values given in kilopascals or megapascals, but they’re still expressed in pascals with a prefix.