Question

what do you mean by the magnitude of a physical quantity solution

Answer 1

Let's come to an instance.
Suppose, an object is kept on x axis having an acceleration of 2m/s sq. Assuming, body is initially at rest, it starts moving.
You would wondering that it must move towards positive x axis. But it's not necessary. I just mentioned that acceleration is 2m/s sq, I didn't comment about its direction.
So, this is the magnitude of the give acceleration which is free of direction given to this physical quantity.

Suppose, the above body has velocity 5m/s at any instant in +ve x axis. Here I m talking about the speed(magnitude of velocity) along with its direction which makes this quantity a pure physical quantity.
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