- #1

Dr.Brain

- 538

- 2

First one is the coulombs Law which is suppose is wrong, because it does not take into account for fact that electrical influences have a speed limit of 'c'.

Second one is the correction factor which I had been looking for

Thord term is a sort of description for radiation.

**My first question:**

1. So how does electric field behave? Does it:

i) Propogate from the charge at 'c' and its strength decreases with distance while propogating.

ii) When a charge is created a field is always there with it, its their property, there is not initial propogation.

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In the book , Feynman says that it is not possible to calculate the

electric field at a certain point because you don't know precisely where the charge is now and at what distance it is now. Also the electric field at a point is due to behavious of charge in the past, you cannot calculate what sthe ELECTRIC FIELD 'now'.So a correction-term is added to the formula of electric field at a point .

**My Second question:**

Is my explanation right?

"Coulomb's Law is perfect for finding electric field at a point only if the charge is at rest or the charge moves infinitesimally slowly, but when the charge is moving , we need to add some 'correction electric field' to make up for the 'r/c' time lost due to field propogation taking time"

BJ