Mass of a body

What do we actually mean by mass of a body? Does mass and weight of the body are the same thing? Why do we usually see mass in numerical problem in physics in spite of seeing weight, to which we are more familiar, we will answer all these queries in these posts.

Mass is generally related to weight, and it is obvious also because more will be the mass more it is difficult of lift it and similarly more is the weight more it is also more difficult to lift it, but in spite of all these similarity from the view of modern scientific understanding it is not a good idea to take mass and weight as a same quantity, actually mass is the measure of inertial of the body, if you don't know what do we mean by inertia please read our next posts. What happens when we take some object which you can't lift here to moon, may be you can lift it there so when if is it then the whole calculation made here for the space craft changes there in moon, is it happens?
No, mass is not changed when we go from one place to another, but weight changes because weight is not equal to mas but it is equal to mass multiplied by acceleration due to gravity.
Weight = mass X acceleration due to gravity
so what is the dimension of weight, yes it is same to that of force. Means weight is not mass but it is a force which is exerted by earth when we are in earth and by moon when we are in moon, and similarly. So it is easier to lift object on moon because moon can't exert more force on a body but earth can exert greater force than moon to the same object.
We generally use mass in the numerical problem because mass does not changes with change in the altitude or planet while weight changes.
Read our next post to know more about mass and weight.