6. A ship is on the surface of the water, and its radar detects a submarine at a distance of

238 feet, at an angle of depression of 23º. How deep underwater is the submarine?

the submarine is 92.994 feet ≈ 93 feet deep from the surface of the water

Step-by-step explanation:

We can think in a triangle where the hypotenuse is the detection distance and the angle with the horizontal surface of water is the depression angle, then the underwater distance is the vertical side of the triangle.

If we denote Ф as the angle of depression, d as the detection distance and x as the unknown depth of the submarine, using trigonometry:

x = d * sin Ф

thus

x = d * sin Ф = 238 feet * sin 23° = 92.994 feet ≈ 93 feet