Division of a physical quantity

[akashpandey]

TL;DR

Division of normal numbers makes sense but what does division of two physical quantity mean.

As we all know that division simply means how many parts of the whole we have (or splitting into equal parts)
1)Example:- if we have 12 apples and there are 3 people so each will get 4 apples right. Easy!
Now my question is how does this definition makes sense in term of physical quantities ?
2)Example:- theta= arc length/radius
So according to first example i say that theta mean number of radiuses in given arc length ?
similarly what can we say about voltage=work/charge ?

 

[anorlunda]

Do you find it strange that we talk about speed as miles per hour (or km per hour)?

 

[Dale]

As we all know that division simply means how many parts of the whole we have (or splitting into equal parts)
1)Example:- if we have 12 apples and there are 3 people so each will get 4 apples right. Easy!
Now my question is how does this definition makes sense in term of physical quantities ?

I just want to point out that apples and persons are perfectly valid physical quantities. So 12 apples / 3 persons is 4 apples/person. That quantity with units of apples/person is a physical quantity representing the number of apples each person has. So you seem to already have an understanding of division of quantities with units.

 

[akashpandey]

Do you find it strange that we talk about speed as miles per hour (or km per hour)?

No,but Is my second example valid if i say it according to definition of division that is
Theta means how many part of radiuses are there in the arc length ?

 

[anorlunda]

No,but Is my second example valid if i say it according to definition of division that is
Theta means how many part of radiuses are there in the arc length ?

Sorry, I don't understand what you are trying to ask.

If A=B/C then C=B/A. So what?

 

[Lnewqban]

...
Now my question is how does this definition makes sense in term of physical quantities ?
2)Example:- theta= arc length/radius
So according to first example i say that theta mean number of radiuses in given arc length ?
similarly what can we say about voltage=work/charge ?

I like calling these cases ratios or relationships rather than divisions.
As the value of arc length increases and/or radius decreases, the value of theta is greater, and vice-versa.
As the value of work increases and/or charge decreases, the value of voltage is greater, and vice-versa.