Hi, Thanks for your time gentlemen
Have you tried understanding the subject rather than just question spotting? It's usually wisest
Yes I have tried understanding the subject and its not question spotting. My understanding is that:
Great circles are straight lines that go all the way around the center of the earth. The equator is a great circle. Meridians of longitude are great circles.
The shorter arc of a great circle between two points is the shortest surface-path between them. The length of the shorter arc is taken as the distance (the great-circle distance) between two points on a surface of a sphere.
Quoting Oxford: Great Circle is a circle on the surface of the earth whose centre and radius are those of the earth itself is called a Great Circle. It is called 'great' because a disc cut through the earth in the plane of the Great Circle would have the largest area that can be achieved.
The shortest distance between two points on the Earth's surface is the shorter arc of the Great Circle joining the two points. Given two points on the Earth's surface, there will be only one Great Circle joining them (unless the points are diametrically opposed).
In question 2, c is the only possible answer even with the unfortunate use of the word added as opposed to applied
b) a correction to be added to magnetic heading to obtain compass heading
c) a correction to be added to compass heading to obtain magnetic heading
Disregarding the "added" phraseology, both options appear to be the same (to me). By applying the correction you can obtain either of the values i.e. magnetic from compass or compass from magnetic. So whats the catch?
1b is the correct answer. Even Mr. Wikipedia knows this :-) (Great-circle distance - Wikipedia, the free encyclopedia see the second pragraph!)
Thanks, as that also confirms
Regards