Signal and Noise: The Basics

One of the first things that physicists learn is that measurements are not exact. In fact, there can be so much variation in data that it is difficult to decide if any important information is there. The variation in data can result from background “noise” which can be caused by particles entering the detector that we are not studying in a particular experiment or from the settings of the instrumentation. This activity has two sections: analysis of signal and noise in everyday audio and video situations, and an introduction to interpreting instrument data and recognizing when a signal is present above the noise.