In mathematics, there are no strict rules regarding how to list length and width. However, there are some conventions or standards used depending on the context of the measurements.
The length and width of an object or space are used to determine an object's area. Additionally, these measurements can be used to measure the perimeter or distance around the edge of the object. If there is a third measurement (depth), the three are used to determine the volume of an object. Labeling the measurements clearly is important so others can get a clear picture of the size and shape of an object. Though there are no strict rules in how to express measurements, there are a few guidelines that people can follow.
Length vs. Width
When looking at a two-dimensional object, it might be difficult to decide which side or measurement refers to the length and which side refers to width. If a person is looking at a rectangular shape, the length should refer to the longest side. One can equate length with the word "long" in this instance. Conversely, width would refer to the shorter side and is used to describe how wide the rectangle is.
Length vs. Height
In terms of dimensions of an object, the terms "length" and "height" might be used interchangeably. Both terms refer to the longest side of the shape. The difference lies in the orientation of the object or shape. If the shape is oriented vertically, then its dimensions are often listed as height and width. If it is oriented horizontally, then the dimensions are listed as length and width. Again, there are no strict rules regarding the terminology. A person should use the pair of terms that make the most sense with the object being described.
Standard Measurements for Objects
Certain situations or scenarios use standard measurement descriptions. For example, when referring to blueprints or the size of a room, the dimensions are listed with width first and length second. Likewise, when measuring windows, the width comes first then the height. Conversely, when expressing the measurements of a painting on canvas, the height comes first then the width. So while there are no strict rules regarding measurements across the board, there are standard measurements for certain objects.
Expressing Measurements in Three Dimensions
Similar naming conventions apply for three-dimensional objects as well. However, the third dimension adds the element of depth. When it comes to listing the measurements of a three-dimensional object, the correct order depends on the object category. Those who are unsure, should be clear with their labels so that others can easily decipher the measurements.
Ultimately, people should remember that clarity is the most important factor to consider when labeling measurements. The idea is to make sure that the measurements are easy to understand by others or easy for the person to remember when referring to them later. In many instances, this means putting the longest measurement or length first by default. However, people should be sure to look up the standard labeling conventions for a specific object. Others use these labeling conventions to get a clear picture of the size or volume of an object.