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In the past, a common time measuring instrument was the sundial. Today, the usual measuring instruments for time are clocks and watches. For highly accurate measurement of time an atomic clock is used. Stopwatches are also used to measure time in some sports.
A nephoscope is a 19th-century instrument for measuring the altitude, direction, and velocity of clouds, using transit-time measurement. This is different from a nephometer, which is an instrument used in measuring the amount of cloudiness.
General purpose instrument measures voltage, current and resistance (and sometimes other quantities as well) Network analyzer: Measures network parameters Ohmmeter: Measures the resistance of a component Oscilloscope: Displays waveform of a signal, allows measurement of frequency, timing, peak excursion, offset, ... Psophometer
Horology is commonly used specifically with reference to the mechanical instruments created to keep time: clocks, watches, clockwork, sundials, hourglasses, clepsydras, timers, time recorders, marine chronometers, and atomic clocks are all examples of instruments used to measure time.
The idea of using atomic transitions to measure time was first suggested by the British scientist Lord Kelvin in 1879, [204] although it was only in the 1930s with the development of magnetic resonance that there was a practical method for measuring time in this way. [205] A prototype ammonia maser device was built in 1948 at NIST. Although ...
Ascent rate times ascent time yields the ceiling height. A disdrometer is an instrument used to measure the drop size distribution and velocity of falling hydrometeors. Rain gauges are used to measure the precipitation which falls at any point on the Earth's landmass.
Instruments come in three main varieties: short period, long period and broadband. The short and long period measure velocity and are very sensitive, however they 'clip' the signal or go off-scale for ground motion that is strong enough to be felt by people. A 24-bit analog-to-digital conversion channel is commonplace.
Weather stations typically have these following instruments: Thermometer for measuring air and sea surface temperature; Barometer for measuring atmospheric pressure; Hygrometer for measuring humidity; Anemometer for measuring wind speed; Pyranometer for measuring solar radiation; Rain gauge for measuring liquid precipitation over a set period ...