Hover or tap underlined Spanish terms to see their translation and exam tip.
Derrota ortodrómica. Distancia entre el punto 65° 33' S, 093° 14' W y 12° 31' N, 169° 56' E.Great-circle sailing: calculate the distance between 65° 33' S, 093° 14' W and 12° 31' N, 169° 56' E.
Show the answer
Correct answer: c) 6252'
Why it is correct
Crossing the antimeridian, ΔL = 360º − (93º 14′ + 169º 56′) = 96º 50′. With latitudes in opposite hemispheres, cos D = −sin(65º 33′) sin(12º 31′) + cos(65º 33′) cos(12º 31′) cos(96º 50′) = −0.24537, giving D = 104.203º = 6252′.
Why the others are not
- a) Treats cos(96º 50′) as positive instead of negative.
- b) Adds the sine term as if both latitudes had the same name.
- d) Makes a sign or rounding error in the formula.
How to work it out in the exam
- Watch both negative signs: opposite-name latitudes and ΔL > 90º.
Where this question comes from
- Junta de Andalucía · 2023 · 1ª convocatoria · CY Módulo de navegación · question 12 Official paper · Official answer key
Pending instructor review. Machine translation, not reviewed.