Work done per unit charge by electric field on charge

[Cicicicici]

Homework Statement

Homework Equations

The Attempt at a Solution

I know the units for V is J/C so #3 and #4 are wrong. But how do I determine the signs?

 

[kuruman]

Is the work done by the electric field positive or negative? What do you need to ascertain in order to answer this question? Hint: When is the work done by a force positive and when is it negative?

 

[Cicicicici]

Is the work done by the electric field positive or negative? What do you need to ascertain in order to answer this question? Hint: When is the work done by a force positive and when is it negative?

Work is positive when force is in same direction as displacement. So here the direction is X to Y and the force is also from X to Y because Vx>Vy?

 

[kuruman]

Work is positive when force is in same direction as displacement. So here the direction is X to Y and the force is also from X to Y because Vx>Vy?

Yes, electric field lines point from a region of high potential to a region of low potential. Since the charge is positive, the electric force on it is in the same direction as the electric field.

 

[Cicicicici]

Yes, electric field lines point from a region of high potential to a region of low potential. Since the charge is positive, the electric force on it is in the same direction as the electric field.

Thank you!