What are Scalar & Vector Quantities?
- A scalar is a quantity which only has a magnitude (size)
- A vector is a quantity which has both a magnitude and a direction
- For example, if a person goes on a hike in the woods to a location which is a couple of miles from their starting point
- As the crow flies, their displacement will only be a few miles but the distance they walked will be much longer
Displacement is a vector while distance is a scalar quantity
- Distance is a scalar quantity because it describes how an object has travelled overall, but not the direction it has travelled in
- Displacement is a vector quantity because it describes how far an object is from where it started and in what direction
- There are a number of common scalar and vector quantities
Scalars and Vectors Table
Examiner Tip
Do you have trouble figuring out if a quantity is a vector or a scalar? Just think - can this quantity have a minus sign? For example - can you have negative energy? No. Can you have negative displacement? Yes!