Hover or tap underlined Spanish terms to see their translation and exam tip.
Si zarpamos del puerto de Tánger (luz del faro del extremo del espigón) con rumbo al puerto de Barbate (luz roja del extremo del espigón) y queremos hacer este recorrido en 3 horas. ¿Qué velocidad de máquinas deberemos de poner?Departing Tangier port (breakwater end light) bound for Barbate port (red light at the end of the breakwater), what speed must you set to complete the passage in 3 hours?
Show the answer
Correct answer: a) 8.1 knots.
Why it is correct
Measuring on the chart the distance between Tangier breakwater light (35º 47.4′ N, 005º 48.2′ W) and Barbate breakwater red light (36º 11.3′ N, 005º 55.3′ W) gives 24.3 miles. Covering that in 3 hours requires speed V = 24.3 / 3 = 8.1 knots.
Why the others are not
- b) Does not match the quotient of the 24.3 miles between Tangier and Barbate divided by 3 hours.
- c) Does not match the quotient of the 24.3 miles between Tangier and Barbate divided by 3 hours.
- d) Does not match the quotient of the 24.3 miles between Tangier and Barbate divided by 3 hours.
How to work it out in the exam
- Measure on the latitude scale the distance between Tangier and Barbate breakwaters: 24.3 miles.
- Divide by 3 hours: V = 24.3 / 3 = 8.1 knots.
Where this question comes from
- Región de Murcia · 2019 · 1ª convocatoria · PER Tipo 1 · question 43 Official paper · Official answer key
Try it: Navigation calculations
Pending instructor review. Machine translation, not reviewed.