why electric field is conservative in nature?explain.

Asked by Shubham Jain | 18th Nov, 2014, 07:36: AM

Expert Answer:

A force is said to be conservative if the work done by the force in moving a particle from one point to another point depends only on the initial and final points and not on the path followed.
The field where the conservative force is felt is called conservative field. Electric field is a conservative field. 
i.e.Consider an electric field due to a charge Q.The work done to carry a test charge q from one point A to another point B in the field due to Q does not depend upon the path followed.It depends only upon the initial and final positions A and B. It will be independent of the path followed .So we say that electric field is conservative in nature.
Conservative nature of electric field means that the line integral of electric field along a closed path is zero.
Consider two point A and B in an electric field due to a charge Q. Work is done by the electric field in moving a test charge from point A to B along a closed path.For that we have to add up the work done for all the infinitesimal segments into which the path A and B is divided. Such an integral evaluated along a line is called a line integral.
 

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i.e.Line integral of electric field along a closed path is zero means that the work done by the electric field is independent of the path and depends only on the end points A and B of integration.

Answered by Jyothi Nair | 18th Nov, 2014, 10:55: AM