How position depends on the choice of a reference point and reference direction?

Answer 1

The answer is so simple and obvious that it's almost impossible to explain. Th e only way I can think of to explain it is with an example.

If I phone you or text you, and I ask you where you are, and you reply "I'm 3 miles.",

you haven't given me any information at all ... I would have no idea where to go

in order to meet up with you.

You would have many many different ways to reply, but that wouldn't be one of them.

Here are a few ways you might answer me:

-- I'm 3 miles north of Jim's house.

-- I'm 1 mile west of school.

-- I'm across the street from the grocery store.

-- I'm on top of Suzie's house.

In fact, ALL of these descriptions might be the same place.

Any time you describe a place, there's always a reference point and a reference direction

from it.

"Jim's house", "school", "the grocery store", and "suzie's house" are all reference points.

"North", "west", "across the street", and "on top" are all reference directions from the

reference point.

Answer 2

The position of an object depends on the choice of a reference point because position is a relative concept - it is the location of the object with respect to the chosen reference point. The reference direction is important because it determines how the position is measured - for example, whether it is measured horizontally, vertically, or along another axis. Changing the reference point or direction will change the reported position of the object.