CDF POINTS
1. Dimensions of a physical quantity are the power to which the base quantities are raised to represent that quantity.
2. The dimensions of a physical quantity describe the nature of the factors by which that quantity depends on the base or fundamental quantity.
3. Dimensional analysis is the practice of checking relations between physical quantities by identifying the dimensions of the physical quantities.
4. The dimensions of fundamental quantities are enclosed in square brackets [ ] to represent its dimensions.
5. Dimension of Length is described as [L]
6. Dimension of time is described as [T]
7. Dimension of mass is described as [M]
8. Dimension of electric current is described as [A]
9. Dimension of the amount of quantity can be described as [mol].
10. Dimension of temperature is [K]
11. Dimension of luminous intensity is [Cd]
12. If a physical quantity is independent of any fundamental quantity, we take its power of dimension of fundamental quantity to be zero.
13. Plane angle and Solid angle are dimensionless quantities.
14. Plane angle and Solid angle are independent of fundamental quantities.
15. Dimensions are used in dimensional analysis& used to convert one system to another system.
16. Dimensions are used in predicting unknown formulae by just studying how a certain physical quantity depends on base quantities and up to which extent.
17. Dimensions can’t be used for trigonometric and exponential functions.
18. A dimensionally correct equation may not be the correct equation always.
19. An expression showing the powers to which the dimensions of fundamental quantities are raised to obtainone unit of the derived quantity is called Dimensional formula of that quantity.
20. The physical quantities which have dimensions and have a fixed value are called as dimensional constants.
21. Dimensional variables are those physical quantities which have dimensions and do not havefixed value.
22. Dimensionless constants are those which do not have dimensions but have a fixed value.
23. Dimensionless variables are those physical quantities which do not have dimensions and donot have fixed value.