Vector and Scalar Quantity

Defining Scalar and Vector Quantity

Scalar is the measurement of a medium strictly in magnitude.

Vector is a measurement that refers to both the magnitude of the medium as well as the direction of the movement the medium has taken.

Scalar Quantities

Scalar quantities, as stated above, are the measurements that strictly refer to the magnitude of the medium. There are absolutely no directional components in a scalar quantity - only the magnitude of the medium.

Time - Scalar quantities often refer to time; the measurement of years, months, weeks, days, hours, minutes, seconds, and even milliseconds.

Volume - Scalar quantity can refer to the volume of the medium, as in how much of the medium is present. Everything from tons to ounces to grams, milliliters and micrograms are all scalar quantities, as long as they are applied to the medium being measured and not the movement of the medium. 

Speed and temperature - Two more commonly used scalar quantities in physical calculations are speed and temperature. As long as they are not associated with a directional movement, they remain scalar quantities. For instance, the measurement of speed in miles or kilometers-per-hour or the measurement of the temperature of the medium both remain scalar quantities as long as they aren’t associated with the direction of the medium’s travel.  

Vector Quantities

Vector quantities, however, refer to both the direction of the medium’s movement as well as the measurement of the scalar quantity.

Increase/Decrease in Temperature - The measurement of the medium’s temperature is a scalar quantity; the measurement of the increase or decrease in the medium’s temperature is a vector quantity.

Velocity - The measurement of the rate at which an object changes position is a vector quantity. For example:

If a person quickly moves one step forward and then one step backward there would certainly be a lot of activity; but, there would be "zero velocity."

In order to measure the vector...