SIGNIFICANT FIGURES AND SYSTEM OF UNITS (Lesson 2.2)

significant

Non-zero digits are always _____

significant

Captive zeroes are always ______

significant

All final zeros after the decimal point are

not significant

Leading zeroes are _______

Significant Figures

This consists of all the digits known with certainty plus one more digit that is uncertain or estimated.

Less than 5

If the number after the last sig. fig is: drop and leave the numbers unchanged.

Greater than 5

If the number after the last sig. fig is: add 1 to the last significant number.

added & subtracted

When measurements are _____ or _____, the answer cannot have more decimal place than those in the least accurate measurement.

multiplication and division

The product contains the same number of figures as the number containing the least sig figs used to obtain it.

Measurement

Is the process of quantifying the properties of an object.

Unit

A fixed quantity with respect to physical quantity is measured is called a _____.

International System of Units (SI)

is the modern form of the metric system and
the world's most widely used system of
measurement.

Physical Quantities

any number that is used to describe a physical phenomenon

Area

(Length x Length)

Volume

(Length x Length x Length)

Speed

(Length / Time )

Force

(Mass x (Length / Time / Time)

Metric System

● Used by the rest of the
world.
● base-10 system.
● Variation : mks and the
cgs sytem
● mks : meter, kilogram,
seconds
● cgs: centimeter, gram ,
seconds.

English System

● Known as customary
system of measurement
● Used in the United States,
Burma and Liberia.
● Also known as the fps
sytem.
● fps : foot , pounds ,
seconds.

System Units

Metric System and English System

SI Units

Based Units and Derived Units

Based Units

Lengths, mass, time, electric current, temperature, amount of substance and luminous intensity.

Derived Units

speed, acceleration, density , work and energy. ed, acceleration
, d

Unit Prefixes

or metric prefix can be used to make a new unit larger or smaller in the base unit.