Scales and Errors Definition: A scale is a representation of a measured quantity on a graphic or diagram. It is used to show the relative size of differ...
Scales and Errors
Definition:
A scale is a representation of a measured quantity on a graphic or diagram. It is used to show the relative size of different objects or distances on a map, plan, or model.
Purpose:
The purpose of using a scale is to ensure that all measurements and distances are accurate and comparable. When using a scale, it is important to pay attention to both the length of the measuring instrument and the markings on the scale.
Types of Scales:
Linear scale: A linear scale is a straight line that represents a constant ratio between corresponding lengths on the map or model and the actual objects or distances.
Planar scale: A planar scale is a curved line that represents a constant ratio between areas of corresponding shapes on the map or model and the actual objects or distances.
Angular scale: An angular scale is a curved line that represents a constant ratio between angles measured in the map or model and the actual angles.
Errors in Measurements:
Measurement error: A measurement error is the difference between the actual value and the measured value.
Systematic error: A systematic error is a consistent bias in the measurements that results in an offset from the true value.
Random error: A random error is a variation in the measurements that results from sampling variability.
Using Scales and Errors:
Measure accurately: Use a calibrated measuring instrument and follow the instructions for using the scale.
Correct for errors: Subtract the measurement error from the actual value to obtain the correct measurement.
Interpret the scale factors: Multiply the measured value by the scale factor to determine the actual value.
Examples:
Linear scale: A map with a scale of 1 inch to 10 feet indicates that for every inch on the map, the actual object or distance is 10 feet long.
Planar scale: A blueprint with a scale of 1/4 inch to 1 foot indicates that for every 4 inches on the blueprint, the actual object or distance is 1 foot long.
Angular scale: A compass with a scale of 1 degree to 10 minutes indicates that for every 1 degree of rotation, the actual angle is 10 minutes