Is it possible to determine the uncertainty of a speedometer?

Yes, it is possible to determine the uncertainty of a speedometer by comparing its readings against a known reference, such as a GPS device or a calibrated speed measurement system. This can help identify any systematic errors or deviations in the speedometer's performance. Additionally, factors such as tire size, calibration errors, and vehicle dynamics can contribute to the overall uncertainty, which can be quantified through repeated measurements and statistical analysis.