Unit AND Dimensions

UNIT AND MEASUREMENT
In our daily life we measure something in our daily basis. For example let your mother told you to buy some rice, and she told you to buy 5 kg rice. But when you reached at shop, you forget the term kg, you only remember 5. Then the shopkeeper asked you that how much rice you want? You told that you want 5 rice. The shopkeeper get confused, and he asked that, “5 what? 5 kg or 5 gram” Here 5 is a number and kg/gram are unit

In this way in our daily life we measure length. Like length of a road, length of cloth, and many more. We measure our height in feet. We measure liquid material like milk, water, cold drinks in liter. These are something we use in our daily life and measure them.

Let’s feel the sense of unit again. Suppose your boyfriend told you that, “ I LOVE YOU” then you ask that how much? And he told you that 10 kg……. Is there any sense of this sentence?

We can’t measure all the things that present in this universe. We only measure the physical quantity present here. We can’t measure the emotion, we can’t measure the feelings of someone, we can’t measure the excitation of some one, because these are not physical quantity.

What is physical quantity?
Those quantities which we can measure are called so. In the world of physics, there are so many things we have to measure. Example — length, mass, time etc etc.

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