Relative Error: Percentage Error

By Janice VanCleave
John Wiley & Sons, Inc.
APPENDIX 2

Purpose: To calculate the relative error of experimental measurements.

Materials

calculator

Procedure

  1. Calculate the average of the measurements. For example, the average of the sample experimental measurements in Table A2.1 is:
  2. Use the following equation to determine the relative error (also called percentage error) of the measurements. For example, if the accepted (known) value for the angle measurement is 29.8°, the relative error for the experimental measurement would be:
  3. where Er is the relative error, Ea is the absolute error (the difference between the known and experimental measurements), and A is the known measurement. Note that Ea is the experimental measurement minus the accepted measurement. For this sample, the absolute error is 29.6° – 29.8° = –0.2°.

    The sign of the absolute or relative error merely indicates whether the result is low (–) or high (+).

Add your own comment

Ask a Question

Have questions about this article or topic? Ask
Ask
150 Characters allowed

Today on Education.com