In physics and engineering, measurement is the activity of comparing physical quantities of real-world objects and events. Established standard objects and events are used as units, and the measurement results in a given number for the relationship between the item under study and the referenced unit of measurement. Measuring instruments are the means by which this translation is made.

Physicists use a vast range of instruments to perform their measurements. These range from simple objects such as rulers and stopwatches to electron microscopes and particle accelerators.

• Mass
  • balance
  • weighing scales
  • mass spectrometer
  • katharometer

History of Weights and Measures

• Time
  • calendar
  • chronometer
  • clock
  • atomic clock
  • radiometric dating

Timeline of time measurement technology

• Length (i.e., distance)
  • altimeter (measures height)
  • architect's scale
  • engineer's scale
  • interferometer
  • micrometer
  • odometer
  • opisometer
  • ruler
  • tape measure
  • laser rangefinder
  • ultrasound distance measure

• Area
  • planimeter

• Angles
  • sextant
  • theodolite
  • protractor

• Temperature
  • thermometer
  • thermocouples
  • thermistors
  • pyrometers
  • electromagnetic spectroscopy

• Humidity
  • hygrometer

• Pressure
  • barometer
  • manometer
  • Pitot tube (used to determine speed)
  • anemometer (used to determine wind speed)
  • tire-pressure gauge

• Flow

• pH

• Level
  • spirit level
  • laser line level

Timeline of temperature and pressure measurement technology

• Sound

• Light

• Speed
  • speedometer
  • airspeed indicator

• Electrical properties
  • electrometer (measures charge)
  • ammeter (measures electrical current)
  • galvanometer (measures current)
  • ohmeter (measures resistance)
  • voltmeter (measures voltage)
  • Wheatstone bridge
  • multimeter (measures all of the above)
  • oscilloscope
  • watt meter (measures power)
  • electric energy meter (measures energy)

• Hardness
  • durometer

• Uncategorized
  • colorimeter (measures absorbance, and thus concentration)
  • geiger counter
  • Nichols radiometer
  • radiometry
  • sicroscope
  • spectrometer
  • spectroscopy is an important tool used by physicists.