9th Class Physics# (2025), Measurement of Physical Quantity# and Interna...
Measurement of Physical Quantities Physical Quantity: A physical quantity is any quantity in physics that can be measured and expressed numerically. Examples include length, mass, time, temperature, current, etc. Types of Physical Quantities: Base Quantities: These are fundamental quantities that cannot be derived from other quantities. There are 7 base quantities in physics: Length (meter, m) Mass (kilogram, kg) Time (second, s) Electric current (ampere, A) Temperature (kelvin, K) Amount of substance (mole, mol) Luminous intensity (candela, cd) Derived Quantities: These are quantities derived from base quantities through mathematical operations. Examples include: Velocity (m/s) Acceleration (m/s²) Force (newton, N = kg·m/s²) Pressure (pascal, Pa = N/m²) International System of Units (SI Units) The International System of Units (SI) is a globally accepted system for measuring physical quantities. It ensures uniformity and consistency in measurements worldwide. Key Features of SI Unit...