The expressions or formulae which tell us how and which of the fundamental quantities are present in a physical quantity are known as the Dimensional Formula of the Physical Quantity. The equations obtained when we equal a physical quantity with its dimensional formulae are called Dimensional Equations. Copy the link given below and paste it in new browser window to get more information on Dimensional Formulae and Dimensional Equations www.askiitians.com/iit-jee-physics/general-physics/dimensional-formulae-and-dimensional-equations/

1. Dimensional Formula and
Equations

2. Dimensional Formulae
 The formulae which are used to define a physical
quantity in terms of fundamental quantities are
called dimensional formulae
 For example dimensional formula of velocity is
[M0LT-1]
 Dimensional formulae of trigonometric,
logarithmic and exponential functions are not
defined as they are dimensionless

3. Applications of Dimensional
Formulae
 In expressing a physical quantity in terms of
fundamental quantity by raising them to certain
powers
 They are used in dimensional analysis in order to
convert units from one system to another

4. Dimensional Equations
 When we equate dimension of a physical quantity
with its dimensional formula we get a dimensional
equation
 For example, dimensional equation of velocity is
given as [v] = [M0LT-1]

5. Limitations
 We can’t predict nature of constants,
trigonometric and logarithm functions with the
help of dimensions
 We can’t find proportionality constants while
deriving relation between different physical
quantities

6. Hey Friend,
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