UPSC 2014 CDS II GK Paper

An oscilloscope is an instrument which allows us to see waves produced by sound. An oscilloscope is a laboratory instrument commonly used to display and analyse the waveform of electronicsignals. It produces an image by causing a focused electron beamto travel or sweep in patterns across the face of a cathode ray tube (CRT). Sound waves are converted into electrical signals and displayed at oscilloscope.