Many of the variables in physics are vectors, and this is often the first class where students get to use vector addition to analyze a situation. This activity is a quick and easy way to introduce the concept of vector addition.
Materials Needed per pair of students:
set of cardstock vectors of different lengths
a piece of chalk
Step 1: Adding Vectors Graphically
Students should work in pairs for this activity. One student should randomly distribute the vectors on the desk in front of the pair of students, the second student is to align them to show graphical vector addition. (I demonstrate the different between translating a vector and rotating a vector when I explain this step with a large vector on the board.)
Step 2: Showing the Resultant
The student who moved the vectors into alignment can then draw the resultant of the vector addition with chalk, making sure to include an arrow head to show the direction of the resultant.
Next, I ask the first student to try all other orders of addition of the vectors to see if the order in which you add vectors effects the size or direction of resultant. Works perfectly every time! Then ask the partners to switch roles until everyone can arrange the vectors head to tail quickly and easily.