A potentiometer is a manually adjustable electrical resistor that uses three terminals. It is a three-terminal resistor with a sliding contact that forms an adjustable voltage divider. If only two terminals are used, it acts as a variable resistor. A potentiometer measuring instrument is essentially a voltage divider used for measuring electric potential (voltage); the component is an implementation of the same principle, hence its name .Potentiometers are commonly used to control electrical devices such as volume controls on audio equipment. For example, in a loudspeaker, a potentiometer is used to adjust the volume. In a television set, computer monitor or light dimmer, it can be used to control the brightness of the screen or light bulb. One terminal of the potentiometer is connected to a power source, and another is hooked up to a ground — a point with no voltage or resistance and which serves as a neutral reference point. The third terminal slides across a strip of resistive material. The user can adjust the position of the third terminal along the resistive strip to manually increase or decrease resistance.
b) Cathode ray oscilloscope
Cathode ray oscilloscope is an electronic-display device containing a cathode-ray tube (CRT) that generates an electron beam that is used to produce visible patterns, or graphs, on a phosphorescent screen. It is a type of electronic test instrument that allows observation of constantly varying signal voltages, usually as a two-dimensional graph of one or more electrical potential differences using the vertical or y‑axis, plotted as a function of time (horizontal or x‑axis). Many signals can be converted to voltages and displayed this way. Signals are often periodic and repeat constantly, so that multiple samples of a signal which is actually varying with time are displayed as a steady picture. Oscilloscopes are commonly used to observe the exact wave shape of an electrical signal. Oscilloscopes are used...
Please join StudyMode to read the full document