Stable cavitation occurs when gas bubbles compress under high pressure and decompress under low pressure. Which option best describes this process?

Stable cavitation occurs when gas bubbles compress under high pressure and decompress under low pressure. Which option best describes this process?

• A. Compressed under high pressure and decompress under low pressure
• B. Expand with increasing frequency
• C. Remain inert and unchanging
• D. Move away from the ultrasound beam

Answer: (A)

The main idea here is how gas bubbles behave when ultrasound creates alternating high and low pressures. In stable cavitation, bubbles don’t violently collapse; instead, they repeatedly oscillate in size, staying intact as they respond to the pressure swings. They compress during the high-pressure part of the ultrasound cycle and expand during the low-pressure part. This pattern—compressing when pressure is high, expanding when pressure is low—best matches the described process. That’s why the option stating compression under high pressure and expansion under low pressure is the correct description. The other options don’t capture the defining oscillatory behavior: expanding with frequency isn’t about the cycle-by-cycle compression/expansion, remaining inert and unchanging contradicts cavitation, and moving away from the beam describes position change rather than oscillation.

The main idea here is how gas bubbles behave when ultrasound creates alternating high and low pressures. In stable cavitation, bubbles don’t violently collapse; instead, they repeatedly oscillate in size, staying intact as they respond to the pressure swings. They compress during the high-pressure part of the ultrasound cycle and expand during the low-pressure part. This pattern—compressing when pressure is high, expanding when pressure is low—best matches the described process.

That’s why the option stating compression under high pressure and expansion under low pressure is the correct description. The other options don’t capture the defining oscillatory behavior: expanding with frequency isn’t about the cycle-by-cycle compression/expansion, remaining inert and unchanging contradicts cavitation, and moving away from the beam describes position change rather than oscillation.