Question

What is the meaning of magnitude in physics ?

Answer 1

Hint: We use the concept of physical quantities and measurement of physical quantities. Study about different types of physical quantities and the measurement of those quantities related with.

Complete step by step answer:
Magnitude of any quantity is a number that gives the idea of how large or big a measurement of a physical quantity is relative to a certain reference value (that reference value is most of the time taken to be zero). Let us explain the term magnitude with a few examples.For say, when we say – A boy travels a distance of \[6\,km\], we mean that he has moved \[6\,km\] from his initial position. Magnitude of this distance is obvious. So, we can see that for scalar quantities the magnitude of any quantity can easily be realized.

Now, let’s take a vector quantity: say- A train moves with \[(3\hat i + 4\hat j)\,m{s^{ - 2}}\] acceleration. Then it is not easily realizable how much acceleration that is actually. Here we can demonstrate the proper use of magnitude. If we calculate the magnitude of it will be \[\sqrt {{3^2} + {4^2}} m{s^{ - 2}} = 5\,m{s^{ - 2}}\]. We can easily realize that the train velocity changes with a rate of \[5\,m{s^{ - 1}}\].

So, in physics the magnitude of any quantity gives us the idea of how large a physical quantity or measurement is with respect to some reference value of the same quantity. In the mathematical aspect, a physical quantity is represented as a combination of a numerical value and a unit. We call the numerical value related with a measurement of any physical quantity as the magnitude of that quantity.

Note: Mathematically the magnitude of any quantity is the modulus of the numerical value given with any measurement. Example-if the measured value of distance travelled by a boy is \[ - 50\,m\]. The magnitude of the value is \[\left| { - 50} \right| = 50\].