AlephZero said:Since you were measuring deflections, something probably moved between each measurement. What sort of force tends to prevent things from moving, in any real-world situation?
socrates_1
Friction?
Studiot said:Many engineers call it "stiction". It is the same reason that we tap any mechanical indicating device that relies on mechanical movement to indicate a value, such as a meter movement a dial gauge, a barometer etc.
http://en.wikipedia.org/wiki/Stiction
Tapping the frame helps to remove any air bubbles or other debris that may be trapped between the beam and the support. This ensures that the beam is in proper contact with the support, resulting in more accurate deflection measurements.
Tapping the frame helps to eliminate any sources of error that may affect the deflection readings. It ensures that the beam is not hindered by any external factors, resulting in more reliable and accurate results.
While it is possible to obtain deflection readings without tapping the frame, it is not recommended. Tapping the frame is a crucial step in the experiment that can significantly improve the accuracy and reliability of the results.
It is important to tap the frame with enough force to remove any air bubbles or debris, but not so hard that it affects the beam's position. A gentle tapping motion should be sufficient.
Tapping the frame is a commonly used method in Deflection of Beam Experiments and has proven to be effective in improving the accuracy of results. While there may be alternative methods, it is recommended to follow the established procedure for best results.