Hover or tap underlined Spanish terms to see their translation and exam tip.
Al cruzar el meridiano 180º hacia el oeste :When crossing the 180º meridian (International Date Line) heading west:
Show the answer
Correct answer: d) We add 24 hours (1 day).
Why it is correct
Crossing the 180° meridian heading west takes the vessel from zone +12W (12 hours behind UT) into zone −12E (12 hours ahead of UT), so the clock time stays the same and the calendar date is advanced by one day (+24 hours / +1 day).
Why the others are not
- a) Clock time does not jump by 12 hours; the date changes by 24 hours (1 day).
- b) You do not subtract 12 hours.
- c) You subtract one day (repeat the date) when crossing 180° heading east.
How to work it out in the exam
- Crossing 180° heading West: add 1 day (+24 h) to the date.
Where this question comes from
- Junta de Andalucía · 2015 · 2ª convocatoria · CY Módulo de navegación · question 8 Official paper · Official answer key
Pending instructor review. Machine translation, not reviewed.