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# Vectors and scalars

4 videos
4A: It’s gym day. Today you are going to run, swim, and lift weights. In physics terms, we can describe these actions in terms of vectors and scalars. For instance, if you throw a discus across a field with a 20-pound force westward, that is an example of a vector: an entity with both magnitude and direction. However, when you show off about how many laps you can swim in an hour, you are referring to speed, a scalar, which does not specify direction. An understanding of vectors and scalar will provide a foundation to many of the other basic concepts in physics.

### Introduction to vectors and scalars

VIDEO 8:39 minutes
Distance, displacement, speed and velocity. Difference between vectors and scalars

### Visualizing vectors in 2 dimensions

VIDEO 12:54 minutes
Visualizing, adding and breaking down vectors in 2 dimensions

### Unit vector notation

VIDEO 9:54 minutes
Expressing a vector as the scaled sum of unit vectors

### Unit vector notation (part 2)

VIDEO 9:13 minutes
More on unit vector notation. Showing that adding the x and y components of two vectors is equivalent to adding the vectors visually using the head-to-tail method