Scientific Measurement

 

A Scientific measurement is a result of a scientific process or experiment, usually expressed in numbers or standard units, that you obtain by measuring something. The scientific name for material is ‘matter’. All the matter occupies space and has what is called ‘mass’. Many properties of matter are quantitative; that is, they are associated with numbers. When a number represents a measured quantity, the units of that quantity must always be specified. 

Scientific Measurement


To say that the length of a pencil is 17.5 for example, is meaningless. However, to say that it is 17.5 centimetres (cm) properly specifies the length. The units used for scientific measurement are those of the metric system. Matter can be measured in terms of time, length and mass.

The metric system, which was first developed in France during the late eighteenth century, is used as the system of measurement in most countries throughout the world.

SYSTÈME INTERNATIONAL D’UNITÉS

In the past, many countries followed their own system of measurement and units. To avoid inconveniences that would result from this difference, a common scientific system of units of measurements became necessary. In 1968, a group of scientists from different countries met at ‘the conférence Générale des Poids et des Mesures (CGPM)’ (General Conference on Weight and Measures). 

The system they recommended came to be known as ‘système International d’Unités’ (International System of units) shortened to S.I. units. The system uses seven base units and all others units are derived from these base units by multiplying or dividing one unit by another without introducing a numerical factor.

NAMES AND SYMBOLS FOR BASE S.I. UNITS.

Physical quantity

Name of Si base unit

Symbol for unit

Length

Mass

Time

Electric current

Thermodynamic temperature

Luminous intensity

Amount of substance

Metre

Kilogramme

Second

Ampere

Kelvin

Candela

Mole

m

kg

s

A

K

cd

mol

Base quantities and units


Scientific Measurement tools

 DERIVED UNITS

Most of the units commonly used are a combination of the basic units. There are given in the table below

Quantity

Unit

Symbol

Velocity

Acceleration

Force

Energy

Frequency

Angle

Area

Volume

Density

Momentum

Pressure

Power

Electric charge

Potential difference

Resistance

Capacitance

metre per second

Metre per second squared

Newton

Joule

Hertz

Radian

Square metre

Cubic metre

Kilogramme per cubic metre

Kilogramme metre per second

Pascal

Watt

Coulomb

Volt

Ohm

Farad

m/s

m/s2

N or kg·m/s2

J or kg·m2/s2

Hz

rd

m2

m3

Kg/m3

Kg·m/s

Pa

W or N·m/s

C

V

Ω

F

Derived quantities and units



Discover more from Education Companion

Subscribe to get the latest posts sent to your email.

Discover more from Education Companion

Subscribe now to keep reading and get access to the full archive.

Continue reading