**PURPOSE: **To demonstrate properties of vectors.

**DESCRIPTION: **Various lengths of magnetic vectors can be affixed in arbitrary positions to a magnetic board. The lengths of the three longer vectors are in the ratio 3:4:5, so that they can form a right triangle. Illustrate vector addition, subtraction, motion of vectors, and commutative properties.

**SUGGESTIONS: **This board is for use in classrooms; blackboards provide magnetic base in lecture halls (Demonstration A2-22).

**REFERENCES: ** (PIRA 1A40.40)

**EQUIPMENT: **Portable vector board with collection of magnetic vectors.

**SETUP TIME: **None.