Question 23Navigation Problems70% to pass
You observe the lower limb of the Sun at a sextant altitude (hs) of 41°29.8' on 11 January. The index error is 2.4' off the arc. The height of eye is 68 feet. What is the observed altitude (Ho)?
AI Explanation
The correct answer is A) 41°39.4'.
To calculate the observed altitude (Ho), we need to apply the following formula:
Ho = hs + IE + (2.04 / √h)
Where:
- hs is the sextant altitude (41°29.8')
- IE is the index error (2.4' off the arc)
- h is the height of eye (68 feet)
Plugging in the values, we get:
Ho = 41°29.8' + 2.4' + (2.04 / √68)
= 41°32.2' + 7.2'
= 41°39.4'
The other options are incorrect because they do not accurately apply the formula to calculate the observed altitude (Ho) based on the given information.
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