# why is the length between to charges in a dipole taken 2a?

### Asked by arindam2129 | 11th Apr, 2017, 12:00: AM

Expert Answer:

### This is purely for convenience. There is no physical significance to do so. When we take the length as 2a, it becomes easier to substitute while calculating electric field, etc. While deriving electric field equation, there is a point to be taken such that mid distance of the dipole is to be taken. So, if we take the length as 'a' then in such cases mid distance will be a/2 and the calculation will become tedious. Hence, for convenience, the length is taken as 2a.

### Answered by Romal Bhansali | 12th Apr, 2017, 03:42: PM

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