Question

the upper unit of the measurement of the instrument is called what in physics
plz reply very important​

Answer 1

Answer:

In the SI system of units, we use the meter to measure length. We use a meter scale to measure lengths equal to a few meters. What about longer distances like from your house to the nearest lake or the river? Likewise what about small lengths like the diameter of a cell or size of an atom? We most certainly can’t use a meter scale or any scale to measure very large and the very small distances. Lets read about the methods for their measurement.

Measurement of Length, Mass and Time

Parallax observed by the Hubble Telescope (Source: Wikipedia)

Measurement Of Large Distances

Distances like the distance of the Sun from the Earth or the distance of, say Alpha Centauri from Earth is measured indirectly by the Parallax method. Parallax is the shift in the position of an object with the shift in the position of the observer.