A class reports an average focal length of for a lens whose accepted focal length is
PHYSICS · Multi-part · CBSE · Physics · Units and Measurements · Units and Measurements
Problem
A class reports an average focal length of 18.0cm for a lens whose accepted focal length is 22.0cm. The standard deviation of the class’s individual focal-length measurements is only 0.3cm.
(a) Describe the difference between random error and systematic error in an experimental context.
(b) Using both the average value and the small standard deviation provided, argue whether the dominant error in this class’s measurements is random or systematic.
(c) Identify two plausible sources of the dominant error you selected in part (b) that are specific to focal-length measurements with lenses, and explain how each source would influence the measured value.
(d) For one of the error sources you listed in part (c), propose a modification to the experimental setup or procedure that would reduce its impact, and explain why your modification would be effective.