If the go-return time is 26 µs, the depth is approximately ______.

If the go-return time is 26 µs, the depth is approximately ______.

• A. 1 cm
• B. 2 cm
• C. 3 cm
• D. 4 cm

Answer: (B)

Go-return time represents how long ultrasound takes to travel to a reflector and back. The total distance covered by the sound during that time is speed × time, and the depth is half of that because the travel is out and back. Using the typical speed of sound in soft tissue, about 1540 m/s, and a go-return time of 26 µs (26 × 10^-6 s): - Round-trip distance ≈ 1540 × 26e-6 ≈ 0.04004 m ≈ 4.0 cm - Depth ≈ 4.0 cm / 2 ≈ 2.0 cm So the depth is about 2 cm.

Go-return time represents how long ultrasound takes to travel to a reflector and back. The total distance covered by the sound during that time is speed × time, and the depth is half of that because the travel is out and back.

Using the typical speed of sound in soft tissue, about 1540 m/s, and a go-return time of 26 µs (26 × 10^-6 s):

• Round-trip distance ≈ 1540 × 26e-6 ≈ 0.04004 m ≈ 4.0 cm

• Depth ≈ 4.0 cm / 2 ≈ 2.0 cm

So the depth is about 2 cm.