SCALAR AND VECTOR QUANTITIESVectorsCP-02Page 2Rev. 0Figure 2 VectorTo help distinguish between a scalar and a vector, let's look at an example where the onlyinformation known is that a car is moving at 50 miles per hour. The information given (50 mph)only refers to the car's speed, which is a scalar quantity. It does not indicate the direction thecar is moving. However, the same car traveling at 50 mph due east indicates the velocity of thecar because it has magnitude (50 mph) and direction (due east); therefore, a vector is indicated.When a vector is diagrammed, a straight line is drawn to show the unit of length. An arrow isdrawn on one end of the line. The length of the line represents the magnitude of the vector, andthe arrow represents the direction of the vector.DescriptionofaSimpleVectorVectors are simple straight lines used to illustrate the direction and magnitude of certainquantities. Vectors have a starting point at one end (tail) and an arrow at the opposite end(head), as shown in Figure 2.ExamplesofVectorQuantitiesDisplacement, velocity, acceleration, and force are examples of vector quantities. Momentumand magnetic field strength are also good examples of vector quantities, although somewhatmore difficult to understand. In each of these examples, the main ingredients of magnitude anddirection are present.