Question

Q.3. How is a measurement expressed?

Answer 1

To express a measurement we need two things =>
1 - Quantity
2- Unit of Quantity

QUANTITY
==========
Quantity is the which we can write or express anything in numbers..For example , if i ask your age , you will reply firstly with some number...So here You are using nimber to quote ur age...so age is a quantity...Similary We have so many quantities around us...Like Mass , Length, Time , Speed , force ,etc all are the examples of quantites...

Skills , feelings , emotions , frienship are not a quantity as you cant express them in numbers...

UNIT
======
Units Make the difference between different quantities, By putting unit just after the quantity , It makes clear us that which quantity we are talking about..

As 2 can be a quantity of any type of unit as

2 Hours
2 Kg
2 Km
2 Newton
etc..,
But see How unit differentiate and actually tells us that which quantity we actually talking about here...

We have many quantities and These quantities are to be measured..So in order to give a measurement of such we Express it as Quantity + Unit....Hope this help...

Answer 2

Answer:

the value of obtained on measuring A quantity is called its magnitude.the magnitude of a quantity is expressed as numbers in its unit.