Chapter 1. Unit and Measurements.

1-       Base Quantity – is a physic quantity that can be measured without need calculation

2-       Derived Quantity – is obtained from derivation of the base quantity or in other

word a combination of two or more base quantity

3-      Prefix Modifiers of the Metric System :-

PREFIX	SYMBOL	FACTOR POWER
Tera	T	1012
Giga	G	109
Mega	M	106
Kilo	k	103
Hecto	h	102
Deca	da	101
Deci	d	10-1
Centi	c	10-2
Mili	m	10-3
Micro	µ	10-6
Nano	n	10-9
Pico	P	10-12

4-      Dimension of derived quantity :-

DERIVED QUANTITY	DIMENSION
Volume	[L]3
Energy	[M][L]2[T]-2
Power	[M][L]-2[T]-3
Acceleration	[L][T]-2
Pressure	[M][L]-1[T]-2
Momentum	[M][L][T]-1