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A physical quantity is a quantity that can be measured. Examples of physical quantities are Length Mass Temperature Time and Energy . Every physical quantity has a numerical size and a unit. All units must be written , even in intermediate working.
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A physical quantity is a quantity that can be measured. • Examples of physical quantities are • Length • Mass • Temperature • Time and • Energy . • Every physical quantity has a numerical size and a unit. All units must be written, even in intermediate working. • Example: 15 m + 12 m = 27 m. • (Not: 15 + 12 = 27 m) Mechanics Measurement
SI Units Scientists around the world agree to use the SI units for measuring physical quantities. The SI units for all other physical quantities can be expressed in terms of these base quantities. Mechanics Measurement
Examples: Volume of a cube = length x length x length Hence, SI unit of volume = SI unit of length x SI unit of length x SI unit of length = m x m x m = m3. Density = Mass / Volume Hence, SI unit of density = SI unit for mass / SI unit for volume = kg m3 Mechanics Measurement
Mechanics Measurement
Mechanics Measurement