PHYSICAL QUANTITY:

 PHYSICAL QUANTITY:

To correlate matter and energy, there are some quantities which need to be measured. These quantities are called physical quantities. Some physical quantities are length, weight, time, force, energy etc.

MAGNITUDE:

The number together with the unit is called the magnitude of a physical quantity. e.g 5 meter, 6 kg,10 sec etc.

BASIC UNITS:

A physical quantity, whatever it may be, can always be expressed in terms of the units of the seven special distinct physical quantities. These are called basic quantities and their units are called basic units

                          Basic Quantities and their Units

No	Basic Quantity	Symbol	Unit	Symbol
1	Length	L	Meter	M
2	Mass	m	Kilogram	Kg
3	Time	t	Second	S
4	Electric Current	I	Ampere	A
5	Temperature	T	Kelvin	K
6	Intensity of Light	L	Candela	Cd
7	Amount of substance	N	Mole	Mol

DERIVED UNITS:

             The units derived from the basic units are called derived units. e.g units of Area, Volume, density,

                velocity etc are called derived units.

                            Derived Quantities and their Units

No	Derived Quantity	Symbol	Unit	Symbol
1	Area	A	Square meter	m2
2	Volume	V	Cubic meter	m3
3	Force	F	Newton	N
4	Work	W	Joule	J
5	Pressure	P	Pascal	Pa
6	Velocity	V	Meter per sec	m/s
7	Acceleration	a	Meter per sq sec	m/s2

Posted in: Physics,physics 9th chapter 2