Units and Measurements Introduction

Study Notes

Introduction to Units and Measurements

Measurement involves comparing a physical quantity with a universally accepted reference standard known as a unit.
Results of measurements consist of a numerical value accompanied by its unit.
A limited number of units can express a vast array of physical quantities due to their interrelated nature.
Fundamental or base quantities have specific units called fundamental units.
Derived quantities are expressed as combinations of base units, resulting in derived units.
The collective system of both base and derived units is referred to as the system of units.

The International System of Units (SI)

Historically, various countries used different measurement systems, including CGS (centimetre-gram-second), FPS (foot-pound-second), and MKS (metre-kilogram-second).
CGS system: Length - centimetre, Mass - gram, Time - second.
FPS system: Length - foot, Mass - pound, Time - second.
MKS system: Length - metre, Mass - kilogram, Time - second.
The current internationally accepted measurement system is the Système Internationale d’Unités (SI).
Developed by the General Conference on Weights and Measures in 1971 for global technical, industrial, and commercial standardization.
SI units utilize a decimal system, facilitating easy and convenient conversions within the system.

Description

This quiz covers the basics of units and measurements, emphasizing the importance of units as internationally accepted standards for expressing physical quantities. Explore how measurements are made by comparing physical quantities to these reference standards and learn about the interrelation of different units.