Echo Sounding (AQA GCSE Physics)

• Echo sounding uses ultrasound to detect objects underwater
• The sound wave is reflected off the ocean bottom
• The time it takes for the sound wave to return is used to calculate the depth of the water
• The distance the wave travels is twice the depth of the ocean
  • This is the distance to the ocean floor plus the distance for the wave to return

Echo sounding is used to determine water depth

Step 1: List the known quantities

• • Wave speed, v = 1500 m/s
  • Time, t = 0.12 s

Step 2: Write out the wave speed, distance and time formula

Step 3: Rearrange the equation to make distance (x) the subject

x = v × t

Step 4: Put known values into the equation

x = 1500 × 0.12 = 180 m

Step 5: Half the distance to obtain the depth

d = 180 ÷ 2

Depth, d = 90 m