Which statement accurately describes a low-Q transducer?

• A. It has a narrow bandwidth.
• B. It has a wide bandwidth.
• C. It has a very long pulse length.
• D. It cannot support multifrequency imaging.

Answer: (B)

Low-Q means the transducer’s energy is not tightly confined to a single frequency; its energy is more readily dissipated, so the frequency response is broad. That broad response shows up as a wide bandwidth. A wide bandwidth allows the emitted and received signal to contain many frequencies, which translates to a short pulse in time and therefore better axial resolution. It also makes multifrequency imaging possible because you can use or extract information across a broad range of frequencies to optimize penetration and detail at different depths. The other statements describe high-Q behavior: narrow bandwidth and long pulse length come from high-Q, and a broad range of frequencies enables multifrequency imaging, not the opposite. So, a low-Q transducer is best described as having a wide bandwidth.