Physical Quantities and Measurement

Short Definition

Physical quantities are properties of a body that can be measured, such as length, mass, time, and temperature.

Detailed Explanation

Physics deals with quantities that describe the physical world. Physical quantities can be classified as fundamental (basic) and derived quantities. Measurement involves comparing a quantity with a standard unit.

Types of Physical Quantities

• Fundamental Quantities: Length (meter), Mass (kilogram), Time (second), Electric current (ampere), Temperature (kelvin), Luminous intensity (candela), Amount of substance (mole)
• Derived Quantities: Speed, Force, Pressure, Energy, Power, etc. (expressed in terms of fundamental quantities)

Measurement

• Use of instruments (meter scale, stopwatch, balance, thermometer)
• Accuracy, Precision, Errors in measurement
• Significant figures

Importance

Understanding physical quantities and proper measurement is fundamental to study and apply all concepts in physics accurately.