Which of the following is a common source of error in pressure measurements?

Ambient temperature is indeed a common source of error in pressure measurements. Pressure measuring instruments can be highly sensitive to temperature changes. When the ambient temperature varies, it can affect the viscosity of the fluids inside pressure measuring devices or change the properties of the materials used in the sensors. For example, as temperature increases, gases tend to expand and this can lead to inaccurate readings if the instrument is not calibrated to account for these changes.

Therefore, temperature compensation is often necessary to ensure the accuracy of pressure measurements. Instruments may require specific calibration adjustments depending on the range of temperatures they'll operate in, which highlights the critical nature of controlling and factoring in ambient temperature during pressure measurement processes.

Other sources of error, such as reference weight calibration, pressure fluctuations, and humidity levels, also affect measurement accuracy, but ambient temperature is recognized as a particularly significant factor in many calibration scenarios.