Position
A position is a measurement of a location within a reference frame. This means that positions can be negative or positive depending on the choice for the reference frame's coordinate system. Depending on which reference point we choose, we can say that the ...
Position
Definition: Position
Position is a measurement of a location, with reference to an origin.
Quantity: Position (\(x\)) Unit name: metre Unit symbol: \(\text{m}\)
A position is a measurement of a location within a reference frame. This means that positions can be negative or positive depending on the choice for the reference frame's coordinate system.
Depending on which reference point we choose, we can say that the school is \(\text{300}\) \(\text{m}\) from Kosma's house (with Kosma's house as the reference point or origin) or \(\text{500}\) \(\text{m}\) from Kevin's house (with Kevin's house as the reference point or origin).
The shop is also \(\text{300}\) \(\text{m}\) from Kosma's house, but in the opposite direction as the school. When we choose a reference point, we have a positive direction and a negative direction. If we choose the direction towards the school as negative, then the direction towards the shop is positive. A negative direction is always opposite to the direction chosen as positive.
The origin is at Kosma's house and the position of the school is \(-\text{300}\) \(\text{m}\). Positions towards the left are defined as negative and positions towards the right are defined as positive.
Note that we could also choose the positive direction to be towards the school. In this case Kosma's house is still \(\text{300}\) \(\text{m}\) away from the school, but it is now in the positive direction.
The origin is at Kosma's house and the position of the school is \(\text{+300}\) \(\text{m}\). Positions towards the left are defined as positive and positions towards the right are defined as negative.
This lesson is part of:
One-Dimensional Motion