Physics Measuring Instruments

A Mach meter combines the functions of the Airspeed Indicator (ASI) and altimeter. It indicates Mach number (ratio of true airspeed to speed of sound) by comparing airspeed data with static pressure (altitude) data, as the speed of sound varies with altitude.

A seismograph records seismic waves produced by earthquakes. Note: it measures earthquake intensity/magnitude, not 'density' - the question has terminology issues.

The Severinghaus electrode is an electrode that measures carbon dioxide. It utilizes a CO₂-sensitive glass electrode in a surrounding film of bicarbonate solution covered by a thin plastic carbon dioxide permeable membrane, but impermeable to water and electrolytic solutes.

A seismograph measures and records earthquake shocks by detecting ground vibrations. It consists of a suspended mass that remains stationary while the ground moves during an earthquake, creating a record of the seismic waves. This helps scientists study earthquake patterns, magnitudes, and epicenters. Seismographs cannot measure temperature, air pressure, or time.

Sampling rate measures how many samples are taken per second, which is a frequency. Frequency is measured in Hertz (Hz), where 1 Hz equals one cycle or sample per second.

A lactometer is an instrument specifically designed to measure the density and purity of milk. It works on the principle that denser milk indicates higher purity and lower water content.

The quinhydrone electrode is a type of redox electrode which can be used to measure the hydrogen ion concentration (pH) of a solution in a chemical experiment. It provides an alternative to the commonly used glass electrode in a pH meter.

The Severinghaus electrode is an electrode that measures carbon dioxide. It utilizes a CO₂-sensitive glass electrode in a surrounding film of bicarbonate solution covered by a thin plastic carbon dioxide permeable membrane, but impermeable to water and electrolytic solutes.

The Clark electrode is an electrode that measures oxygen on a catalytic platinum surface.

Yes, it is an instrument to tell the direction of the wind.

A knot is indeed a measure of speed for ships (and aircraft). One knot equals one nautical mile per hour, which is approximately 1.852 km/h or 1.151 mph. It has been used in maritime navigation for centuries and is based on the length of a nautical mile.

The Severinghaus electrode is an electrode that measures carbon dioxide (CO₂). It utilizes a CO₂-sensitive glass electrode in a surrounding film of bicarbonate solution covered by a thin plastic carbon dioxide permeable membrane, but impermeable to water and electrolytic solutes. The carbon dioxide pressure of a sample gas or liquid equilibrates through the membrane and the glass electrode measures the resulting pH of the bicarbonate solution.

A sphygmomanometer is the medical device used to measure blood pressure, consisting of an inflatable cuff to restrict blood flow and a mercury or aneroid manometer to measure the pressure. It was invented by Samuel Siegfried Karl Ritter von Basch in 1881 and improved by Harvey Cushing in 1901.

The Richter scale is the standard instrument used to measure the intensity or magnitude of earthquakes. It was developed in the 1930s and provides a logarithmic scale to quantify earthquake strength.

Fathometer instrument is used to measure the depth of oceans.