Work Done By the Electric Field

AI Thread Summary
To bring a 3 C point charge from infinity to a point X with a change in electric potential of -6 V, the work calculated is -18 J. There is confusion regarding whether this work represents the work done by the electric field or by an external force. The consensus is that this value reflects the work done by an external force to move the charge against the electric field. The work is necessary to overcome the electric field's influence, assuming the charge starts and ends at rest. Clarification on this distinction is essential for understanding electric field interactions.
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Homework Statement


How much work is required to bring a 3 C point charge from infinity to a point X. The change in electric potential from infinity to point X is -6 V.


Homework Equations


-QV=W



The Attempt at a Solution


The answer is -18 J. MY confusion is whether this is the work done by the electric field or an external force? My guess is it is the work done by an external force, however my book says different? Or maybe I'm misinterpreting the question can you confirm that it's an external force?
 
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Assuming the charge starts and ends its journey at rest, it is the work you have to do to overcome the force of the electric field in bringing that charge to X.
 

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