Hover or tap underlined Spanish terms to see their translation and exam tip.
Sabiendo que el 15 de septiembre de 2020 se ha tomado una altura instrumental del limbo inferior del sol de 38°30,0´, que el observador está a una altura de 7,85 metros y que el cero del tambor micrométrico del sextante queda a 0,2´sobre el cero del nonius. Calcular la altura verdadera del sol.On 15 September 2020 the Sun's lower-limb sextant altitude is 38° 30.0', height of eye is 7.85 m, and the zero of the micrometer drum lies 0.2' above the zero of the vernier. Calculate the Sun's true altitude.
Show the answer
Correct answer: a) 38° 40.0'
Why it is correct
With Ci = +0.2′, dip for 7.85 m (−5.0′), and the September lower-limb Sun correction at 38º (+14.8′), the net correction is +10.0′. Added to 38º 30.0′, that gives av = 38º 40.0′.
Why the others are not
- b) Forgets to subtract the 5.0′ dip of the horizon (38º 30′ + 15′ = 38º 45′).
- c) Subtracts 1′ too much in the corrections.
- d) Value unrelated to the problem data.
How to work it out in the exam
- Dip for 7.85 m = −5.0′; Sun correction ≈ +15.0′ → net +10.0′.
Where this question comes from
- Ministerio de Transportes (Madrid) · 2020 · Convocatoria de diciembre · CY Test 1 · question 20 Official paper · Official answer key
Pending instructor review. Machine translation, not reviewed.