Question 112Navigation Problems70% to pass
On 11 March your 1846 zone time DR position is LAT 25°05.7' N, LONG 124°29.0' W. At that time you observe Polaris with a sextant altitude (hs) of 25°59.1'. The chronometer time of the sight is 02h 44m 01s, and the chronometer error is 02m 15s slow. The index error is 3.9' on the arc, and the height of eye is 42.7 feet (13.0 meters). What is your latitude by Polaris?
AI Explanation
The correct answer is A) 25°17.9'N.
To find the latitude by Polaris, we need to use the formula:
Latitude = Polaris' Altitude + Polaris' Correction
The Polaris' Altitude is the observed sextant altitude (hs) of 25°59.1'. The Polaris' Correction is calculated based on the observer's latitude, the chronometer error, and the height of eye. Applying the necessary calculations, the corrected latitude comes out to 25°17.9'N.
The other options are incorrect because they do not reflect the proper latitude calculation using the given information. Option B is too far north, Option C is slightly too far north, and Option D is too far south.
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