Work Done By the Electric Field

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SUMMARY

The work required to bring a 3 C point charge from infinity to a point X with a change in electric potential of -6 V is calculated using the equation W = -QV, resulting in -18 J. This value represents the work done by the electric field, not an external force. The confusion arises from interpreting whether the work is performed by the electric field or an external force; however, it is definitively the work done by the electric field when moving the charge from infinity to point X.

PREREQUISITES
  • Understanding of electric potential and electric fields
  • Familiarity with the equation W = -QV
  • Knowledge of point charges and their behavior in electric fields
  • Basic principles of work and energy in physics
NEXT STEPS
  • Study the concept of electric potential energy in electrostatics
  • Learn about the relationship between electric fields and forces on charges
  • Explore the implications of work done by electric fields in different scenarios
  • Investigate the differences between conservative and non-conservative forces in physics
USEFUL FOR

Students studying electromagnetism, physics educators, and anyone interested in understanding the principles of electric fields and potential energy.

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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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