How does the compass react to being away from the magnetic bar?

The simplest compass is a magnetized metal needle mounted in such a way that it can spin freely. (You can make one yourself by magnetizing an ordinary needle, placing it carefully on a slice of cork, and letting the cork float in a tray of water.) Left to its own devices, the needle turns until one end points north and the other south. You can usually figure out which end is which from the position of the Sun in the sky, remembering that the Sun rises in the east and sets in the west. So if you're looking down on the floating needle at about noon, with the eye on the left and the point on the right, and the Sun in front of you, you know the point is indicating north.

Well the magnitude of its acceleration related to that car starts with the oil change like when you have to change the oil in your car you have to make sure that your precious car is starting really propley and very well