Measurements Units and Errors

 Physical Quantities:-  Anything which can be expressed in number is called Quantity. Different events in nature take place in accordance with some laws. Revealing these laws of nature from the observed events, we need some quantities which are known as physical quantities e.g., length, mass, temp, time, force, speed, acceleration, velocity, etc.

Types of Physical Quantities:-

i) Fundamental or Base Quantities

ii) Derived Quantities

iii) Scalar Quantities

iv) Vector Quantities

v) Supplementary Quantities


Units:- To measure a physical quantity, a standard value of some physical quantities is used, which indicates that, how many times the standard physical quantities is used to measure the whole physical quantities.

System of Units:- 

i) MKS System

ii) CGS System

ii) FPS System

ii) SI System

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