[물리1][정리중][modifying]CH1 Units and Significant Figures

CH1 Units and Significant Figures

1.     International System of Units (SI)

7 SI base units

Base Quantity	Base Unit
Length	meter (m)
Mass	kilogram (kg)
Time	second (s)
Electric Current	ampere (A)
Temperature	Kelvin (K)
Amount of Substance	mole (mol)
Luminous Intensity	candela (cd)

Mechanics is based on MKS(meter-kilogram-second)system.

2.     Significant Figures

1)     The leftmost nonzero digit is the most significant digit.

2)     If there is no decimal place, the rightmost nonzero digit is the least significant digit.

3)     If there is a decimal point then the right most digit is the least significant digit even if it is a zero.

4)     All digits between the least and most significant digits are counted as significant digits.