A colorimeter is a device used in colorimetry. In scientific fields the word generally refers to the device that measures the absorbance of particular wavelengths of light by a specific solution. This device is most commonly used to determine the concentration of a known solute in a given solution.
(1) Wavelength selection (2) Printer button (3) Concentration factor adjustment (4) UV mode selector (Deuterium lamp) (5) Readout (6) Sample compartment (7) Zero control (100% T) (8) Sensitivity switch (9)ON/OFF switch
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Calibration is the activity of checking, by comparison with a standard, the accuracy of a measuring instrument of any type. It may also include adjustment of the instrument to bring it into alignment with the standard. The device with the known or assigned correctness is called the standard. The second device is the unit under test, test instrument, or any of several other names for the device being calibrated.
An instrument used for direct measurement of the electrical resistance of a material or electronic component, usually in ohms. Ohmmeters typically use an ammeter to measure current through the material after it has been given some set voltage by the ohmmeter; the direct-current resistance of the sample can then be directly determined through Ohm's law. Resistance is measured in ohms. It can be calculated from the potential difference across a component and the current flowing through it. The total resistance of a series circuit is the sum of the resistances of the components in the circuit.
Resistors, filament lamps and diodes produce different