Unit 2: Exploring Diversity of Matter by their Physical Properties - Key Terms

Vocabulary flashcards covering key terms about physical quantities, SI base and derived quantities, and common measuring instruments mentioned in the notes.

Physical quantity

A quantity that can be measured and provides information about the physical world; it has a numerical magnitude and a unit.

Magnitude

The numerical value of a physical quantity.

Unit

A standard used to express the magnitude of a physical quantity.

SI base quantity

One of the seven fundamental physical quantities in the SI system, each with its own base unit (e.g., length, mass, time, electric current, temperature).

Length

Base quantity representing distance; SI unit is the metre (m).

Mass

Base quantity representing the amount of matter; SI unit is the kilogram (kg).

Time

Base quantity representing duration; SI unit is the second (s).

Electric current

Base quantity representing the flow of electric charge; SI unit is the ampere (A).

Thermodynamic temperature

Base quantity representing temperature; SI unit is the kelvin (K).

Base quantity

A fundamental quantity in SI with its own base unit.

Derived quantity

A physical quantity obtained from base quantities; examples include speed, area, volume, and density.

Speed

Distance traveled per unit time; SI unit is metres per second (m/s).

Area

Surface measure equal to length × breadth; SI unit is square metres (m^2).

Volume

Amount of space occupied; SI unit is cubic metres (m^3) (also cm^3 or mL for practical measurements).

Density

Mass per unit volume; SI unit is kilograms per cubic metre (kg/m^3).

Luminous intensity

Brightness of a light source; SI unit is the candela (cd).

Kilogram

SI base unit of mass.

Gram

Unit of mass equal to one thousandth of a kilogram (g).

Tonne

Unit of mass equal to 1000 kilograms (t).

Measuring cylinder

Instrument used to measure the volume of liquids; readings depend on the division marks and meniscus.

Electronic balance

Instrument used to measure mass; typical precision about 0.1 g (some balances 0.01 g).

Tape measure

Measuring tool for length; commonly reads with precision around 0.1 cm.

Vernier calipers

Precision measuring instrument for lengths; typical precision around 0.1 mm or 0.01 cm.

Digital calipers

Electronic calipers that display measurements; can measure inner/outer diameters and depths; commonly precise to about 0.01 cm (0.1 mm).