Basic electrostatics's potential difference question.

AI Thread Summary
The discussion centers on the work done by external forces when moving a unit positive charge between two points with different electric potentials, Va and Vb. It asserts that the work done is equal to the potential difference, expressed as Vb - Va. The participant attempts to clarify this by applying numerical values, concluding that moving a charge from a lower to a higher potential requires work, thus supporting the statement as true. The conversation also requests a more detailed explanation using proper variables and formulas to enhance understanding. Overall, the main focus is on understanding the relationship between work, electric potential, and the movement of charges in electrostatics.
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Homework Statement



true false

Work done by external forces in moving a unit positive charge from A at potential Va to B at potential Vb is Vb-Va

Homework Equations



basic electrostatics.

The Attempt at a Solution



dW -F.dr=-Dw
if a unit charge move from Va to Vb then change in potential energy will Vb-Va. So dV=Vb-Va so dW=Va-Vb
 
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Sometimes it might help to throw in some numbers. Let Va be 1 volt and let Vb be 2 volts. If we are moving the positive charge from a to b then we are doing work, so it looks like the answer is true?
 
Spinnor said:
Sometimes it might help to throw in some numbers. Let Va be 1 volt and let Vb be 2 volts. If we are moving the positive charge from a to b then we are doing work, so it looks like the answer is true?

Can you please explain it with proper variable and formulas.
 

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