2 - Scientific Measurement

Measurement

a number that shows the size or amount of something usually in reference to a standard measurement

Measurement

a process of determining how large or small a physical quantity is as compared to a basic reference quantity of the same kind

• Number

• Unit

A measurement is consist of:

Number

which tells the amount (how many or how much)

Unit

which tells the scale of measurement

Metric system

is the standard system based on decimal values. It has unit conversions based on the powers of 10.

• tera

• giga

• mega

• kilo

• deci

• centi

• milli

• micro

• nano

• pico

Metric System prefixes:

English system

a system of measurement based on foot, pound, and seconds (fps)

English system

helps to measure the bigger units without the need for external measuring tools

International System of Units (SI)

is the system that is used as universal standard for measurements

Système International

SI - abbreviation for ___________

• Fundamental

• Derived

Quantities of Measurement:

Fundamental quantities

independent on other quantities for their measurement

Derived quantities

dependent upon other fundamental quantities for their measurement

• Length

• Mass

• Time

• Electric Current

• Temperature

• Amount of substance

• Luminous intensity

SI Base units: (7)

• Area

• Volume

• Density

• Concentration (molarity)

• Speed

Derived units:

Significant figures

are the number of digits in a value, often a measurement, that contribute to the degree of accuracy of the value.

Accuracy

refers to how close a determined value is to the true value

Precision

refers to the closeness by which values agree within a series of measurements of the same parameter

Low accuracy, Low precision

High accuracy, Low precision

Low accuracy, High precision

High accuracy, High precision

significant

Zeros between nonzero digits are ________.

not significant

Leading zeros are _______.

significant

Trailing zeros to the right of the decimal point are ______.

significant

Trailing zeros in a whole number with decimal shown are ______.

not significant

Trailing zeros in a whole number without decimal shown are ______.

Dimension analysis

a problem-solving method that uses the fact that any number or expression can be multiplied by one without changing its value.

F = (1.8)(°C)+32

How to get °F

C = F - 32 / 1.8

How to get °C

K = C + 273.15

How to get °K

R = F + 460

How to get °R