What is Unit in Physics? | Types of Unit in Physics | New Topic [2024]

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Author Name: Arun Paul.

What is Unit in Physics?

The standard amount of a physical quantity chosen to measure the physical quantity of same kind is called unit of that quantity.

Types of Unit in Physics

The physical unit can be classified into two ways

1. Fundamental units: Those units which can neither be derived from another nor they can be further resolved into any other units are called fundamental unit, e.g., metre, kilogram, Kelvin etc.
2. Derived units: The units of all physical quantities which can be obtained from fundamental units are called derived units, e.g., units of speed ms^–1 can be derived from fundamental unit i.e., unit of length and time as Speed = distance/time, so the unit of speed is m/s

Characteristic of Unit

The chosen unit should have the following characteristics:
1) It should be suitable, i.e., neither too small nor too large when compared to the quantities to be measured.
2) It should not vary with time.
3) It must be well-defined.
4) It should be capable of being reproduced easily.
5) It should not depend on physical conditions like, pressure, volume, temperature, etc.
6) It should have international acceptance.