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 Physical quantities Conversion of units Length Length-Measurement Micrometer Micrometer - Pitch Micrometer - Least count Micrometer - Zero error Micrometer - Data Table Time Multiples / submultiples of time Stop-clock Standard form Parallalax error Simple pendulum Amplitude of simple pendulum Time period of simple pendulum Frequency of simple pendulum

## Physical quantities

The foundation of physics rests upon physical quantities in terms of which the laws of physics are expressed.

Therefore, these quantities have to be measured accurately.

Among these are mass, length, time velocity, force, density, temperature, electric current, and numerous others.

Physical quantities are often divided into two categories: base quantities and derived quantities.

Derived quantities are those whose definitions are based on other physical quantities. Velocity acceleration and force etc. are usually viewed as derived quantities.

Base quantities are not defined in terms of other physical quantities.

The base quantities are the minimum number of those physical quantities in terms of which other physical quantities can be defined.

Typical examples of base quantities are length, mass and time.

 Sarika Said : out put is given in the book which u have copied.so it was not useful. 06/05/17 06:20 AM

 yo mama Said : well it is informative but out of date but otherwise helpful 30/03/16 09:56 PM

 Edward Said : Very good helped me so much!!! 14/03/15 02:30 PM

 Cara Delivingne Said : This website is very helpful. However, there are still a few changes you can make to it, now that the syllabus has completely been modified. Thank you for your notes though! Xx 11/12/14 08:34 PM

 zuhi Said : where are the SI units,symbols,Prefixes,and diagrams ? 27/09/14 09:05 AM

 ghost Said : bluffmaster u will find past papers at www.xtremepapers.com 22/09/14 11:12 AM

 Daisy Said : I like ur comment Muffin :) 15/02/14 12:05 PM

 Bluffmaster Said : Good informative. But no past papers, no experiments. This is not IGCSE! You should improve this site. 15/02/14 12:04 PM

 bituu darak Said : Good information try to give all round info for vernier calliper and other important Info 05/09/13 11:29 AM

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 whatever Said : you are wierd dumbass 08/05/12 10:46 PM

 shaheer salim Said : there s a mistake its 1cm(square) = 100 mm(square) 01/03/12 01:04 AM