 Hello and welcome to the session. In this session, we are going to discuss dimensional analysis, fundamental and derived quantities. Let us start with the definition of dimension. Dimensions are the physical properties or quantities which can be measured. Some of the basic dimensions are length, mass, time and temperature. The symbol of length is capital L in square brackets, the symbol of mass is capital M in square brackets, the symbol of time is capital T in square brackets and the symbol of temperature is theta in square brackets. Now let us discuss the definition of units. A unit is a scale used to measure physical quantities of same kind. For example, length is measured in meter, kilometer, centimeter, foot etc. mass is measured in kilograms, grams, pounds etc. Time is measured in seconds, minutes, hours and temperature is measured in Kelvin degrees or Fahrenheit. Let us discuss fundamental quantities. These are basic physical quantities and they are also called base quantities. Following are the fundamental quantities along with their SI unit. The first is length whose symbol is capital L within square brackets and the SI unit of length is meters. Then is mass whose symbol is capital N in square brackets and the SI unit is kilograms. Then is time whose symbol is capital T in square brackets and its SI unit is seconds. Then is temperature whose symbol is theta in square brackets and its SI unit is Kelvin. Then is electric current whose symbol is capital A in square brackets and its SI unit is ampere. Then is luminous intensity whose symbol is small L in square brackets and its SI unit is candela. And lastly is amount of substance whose symbol is small N in square brackets and its SI unit is mole. Now let us discuss derived quantities. There are some quantities which are derived from basic physical quantities or dimensions. These are called derived quantities. Following are some of the derived quantities that is area, volume, speed, density and acceleration. The dimension of area is L square and its SI unit is square meter. The dimension of volume is L cube and its SI unit is cubic meter. The dimension of speed is LT raised to power minus one and its SI unit is meters per second. The dimension of density is ML raised to power minus three and its SI unit is kilogram per cubic meter and the dimension of acceleration is LT raised to power minus two and its SI unit is meter per second square. Thus in this session we have discussed about fundamental and derived quantities. This completes our session. Hope you enjoyed the session.