Work done per unit charge by electric field on charge

In summary, the conversation discusses determining the signs for the units of V and determining the direction of work done by the electric field. It is mentioned that work is positive when the force is in the same direction as displacement, and since the charge is positive, the electric force is also in the same direction as the electric field.
  • #1
Cicicicici
15
0

Homework Statement


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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?
 

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  • #2
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?
 
  • #3
kuruman said:
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?
 
  • #4
Cicicicici said:
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.
 
  • #5
kuruman said:
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!
 

1. What is meant by "work done per unit charge by electric field on charge"?

Work done per unit charge by electric field on charge is a measure of the energy transferred to an electric charge as it moves through an electric field. It is represented by the formula W/Q, where W is the work done and Q is the charge.

2. How is work done per unit charge calculated?

Work done per unit charge is calculated by dividing the work done on an electric charge by the magnitude of the charge. This gives the amount of energy transferred to the charge per unit of charge.

3. What is the unit of measurement for work done per unit charge?

The unit of measurement for work done per unit charge is joules per coulomb (J/C). This represents the amount of energy transferred to a charge of one coulomb as it moves through an electric field.

4. How is work done per unit charge related to electric potential?

Work done per unit charge is directly related to electric potential. The electric potential is the amount of work done per unit charge in bringing a test charge from infinity to a specific point in an electric field. In other words, electric potential is a measure of the work done per unit charge by the electric field on a charge.

5. Why is work done per unit charge important in understanding electric fields?

Work done per unit charge is important because it helps us understand the strength and direction of an electric field. The magnitude of this quantity gives us an idea of how much energy is transferred to a charge as it moves through the field, and the direction of the quantity tells us the direction in which the electric field is pushing or pulling the charge.

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