QUANTITIES AND UNITS Afit Sutiyawan, S.Pd

Environmental

Apabila di sebuah ruang tunggu praktek dokter di kotamu ada seorang yang akan memeriksakan anaknya bercerita berulang-ulang dengan nyaring bahwa, Ia semalam telah mengukur suhu badan anaknya menggunakan barometer, ternyata suhu badan anaknya 40 kg

What was the reaction of other people who heard that

statement?

Physical Quantities

Something that can be measured and the results can be expressed with the value and units called Physical Quantities

Quantities

Principal Quantities

Derivatives Quantities

Principal Quantities

Quantities of principal is the amount that had been established and is the basic quantities, quantities of goods consisting of seven quantities:NO Principal Quantities Unit Abbreviation Dimension

1 length Meter m L

2 Mass Kilogram kg M

3 Waktu Time Second s T

4 Electric current Ampere A I

5 Temperature Kelvin K θ

6 Light Intensity Candela Cd j 7 Number of

Substance Mole mol N

Dimension

Dimension is defined the way it was composed by the mass quantities of goods.

Use Dimensions: To reduce the force of a magnitude To investigate the truth of a formula or

equation

Derivatives Quantities

Derivatives Quantities is defined as the quantities are converted or derived from the principal quantitiesNO Principal Quantities Rumus Formula Dimension

1 Wide length x width [L] 2 2 Volume length x width x height [L] 3

3 Density Mass : Volume [M] [L] -3

4 velocity  space : time [L] [T] -1 5 Acceleration  velocity : time [L] [T] -2 6 Force mass x acceleration [M] [L] [T] -2

7 Work and Energy force x displacement [M] [L] 2 [T] -2

8 Impulse and Momentum

force x time [M] [L] [T] -1

Standard of Units Unit of Mass => a cylinder made of

platinum iridium, which is stored in the Bureu of international weights and measures in Sevres

Unit of Length => the distance of light (in vacuum) at intervals 1/299.792.458 seconds.

Unit of Time => time required cesium-133 atom vibrates 9,192,631,770 times

Unit of Temperature => temperature of the melting point of ice at 76 cmHg is T = 273.15 K, the temperature of the boiling point of water at 76 cmHg is T = 373.15 K

Standard of Units

Unit of electric current => amount of electric charge of one coulomb (1C = 6.25 x 10 18 electrons) that passes through a cross-section in one second

Unit of light intensity => black body width of 1 m 2 a temperature melting point of platinum (1773 0 C) will emit light in a direction perpendicular to a strong and light for 6 x 10 5 candela.

Units of amount of substance => one composed of 6.025 mol x 10 23 particles