Dimensional Formula
Dimensional formula is nothing but an expression that shows how the fundamental units and which of the fundamental units are required to represent the unit of physical quantity.
The process of writing of a dimensional formula of a physical quantity is by enclosing the symbols of the base quantities with appropriate power in square brackets.
Dimensions of fundamental physical quantities along with their dimensional symbols are written as –
- [M] for Mass
- [L] for Length
- [T] for Time
- [I] for Electric Current
- [θ] for Temperature
- [J] for Luminous intensity
- [N] for Amount of substance
Dimensional Formulas for Physical Quantities
Some of the examples of dimensional formulas are as follows:
Physical Quantity with Formula |
Dimensional Formula |
---|---|
Area = Length × Breadth |
[L × L] = [L2] = [M0L2T0] |
Volume = Length × Breadth × Height |
[L × L × L] = [L3] = [M0L3T0] |
Speed = Distance/Time |
[L]/[T] = [LT-1] = [M0L1T-1] |
Velocity = Displacement/Time |
[L]/[T] = [LT-1] = [M0L1T-1] |
Acceleration = Velocity/Time |
[LT-1]/[T] = [LT-2] = [M0L1T-2] |
Pressure = Force/Area = (Mass × Acceleration)/Area |
[MLT-2]/[L2] = [ML-1T-2] |
Force = Mass × Acceleration |
[M] [LT-2] = [MLT-2] |
Work = Force × Displacement |
[MLT-2] [L] = [ML2T-2] |
Kinetic Energy = 1/2 × Mass × (Speed)2 |
[M] [LT-1]2 = [ML2T-2] |
Potential Energy = Mass × Acceleration due to gravity × Height |
[M] [LT-2] [L] = [ML2T-2] |
Impulse = (force x time) |
[MLT-1] |
Units and Dimensions
Units and Dimensions is a fundamental and essential topic in Physics. For the measurement of a physical quantity, Unit plays a vital role. Unit provides a complete idea about the measurement of a physical quantity. Dimension is a measure of the size or extent of a particular quantity.
In this article, we will learn Units and Dimensions related all details including definition, fundamental and derived units, system of units, List of Units of physical quantities, Dimension formula, List of physical quantities and their dimensions, etc.
Table of Content
- What are Units?
- Fundamental and Derived Units
- What are Dimensions?
- Dimensional Formula
- Dimensionless Quantities