Hover or tap underlined Spanish terms to see their translation and exam tip.
En situación: 35°00.3´N; 019°02,0´E, y sabiendo que el Sol tiene un horario en Greenwich corregido (hGc) de 300°13,2´ y una declinación corregida de + 23°25,5´. Se pide determinar el valor de la altura del astro.In position 35° 00.3' N, 019° 02.0' E, given that the Sun's corrected Greenwich hour angle (hGc) is 300° 13.2' and its corrected declination is +23° 25.5', find the Sun's computed altitude.
Show the answer
Correct answer: a) 52° 53.3'.
Why it is correct
The local hour angle is hL = 300º 13.2′ + 19º 02.0′ = 319º 15.2′, so the meridian angle is P = 360º − 319º 15.2′ = 40º 44.8′ E. Using sin a = sin l sin d + cos l cos d cos P gives sin a = 0.79746 and a = 52º 53.3′.
Why the others are not
- b) Subtracts the first term as if latitude and declination had opposite names.
- c) Subtracts east longitude from the Greenwich hour angle instead of adding it.
- d) Uses hGc directly as the meridian angle without applying longitude.
How to work it out in the exam
- In east longitude, hL = hG + L; if hL > 180º, P = 360º − hL (E).
Where this question comes from
- Ministerio de Transportes (Madrid) · 2019 · Convocatoria de junio · CY Test 1 · question 20 Official paper · Official answer key
- Ministerio de Transportes (Madrid) · 2019 · Convocatoria de junio · CY Test 2 · question 17 Official paper · Official answer key
Pending instructor review. Machine translation, not reviewed.