# Concept of Potential Energy -vs Electric Potential in an EField

• Schoomy
In summary, the movement of a positive charge in an electric field will result in it moving towards a position with higher potential and higher potential energy. This is the opposite of what would happen for a negative charge. The concept of potential is defined as potential energy divided by charge, and a higher potential means a higher potential energy for a positive charge and a lower potential energy for a negative charge.
Schoomy

## Homework Statement

6. A positive charge is initially at rest in an electric field and is free to move. Which of the following statements is true about the movement of the positive charge?
a. Start to move to a position with higher potential and higher potential energy
b. Start to move to a position with higher potential and lower potential energy
c. Start to move to a position with lower potential and higher potential energy
d. Start to move to a position with lower potential and lower potential energy

Ok, I know if it were a NEGATIVE charge initially at rest in an electric field, it would do:
B, higher potential, lower potential energy.

What's the answer behind this question though? How does it change for a positive charge? I don't understand the underlying concept of what is going on.

I thought for Potential Energy, for both it would have to be moving to LOWER potential energy, as regardless of it being positive or negative, it is initially at rest (all potential energy) and begins to move (thus potential energy must LOWER given Kinetic=Potential).

However, what would happen for the potential? What is potential? I know it's defined as Potential Energy/Charge

but what does this mean? What's the idea behind it?

Thanks!

Hi Schoomy!
Schoomy said:
However, what would happen for the potential? What is potential? I know it's defined as Potential Energy/Charge

Yes, so higher potential means higher potential energy if the charge is positive, and lower potential energy if the charge is negative.

I can explain the concept of potential energy and electric potential and how they relate to the movement of a positive charge in an electric field.

Potential energy is the energy an object has due to its position or state. In the case of a positive charge in an electric field, the potential energy is related to its position in the field. The higher the potential energy, the more work is required to move the charge to a different position in the field. This is because the charge experiences a force in the direction of the electric field, and work is done when the charge moves in the direction of the force.

On the other hand, electric potential is a measure of the potential energy per unit charge at a specific point in the electric field. It is like a "map" of the potential energy distribution in the field. The electric potential at a given point is determined by the strength of the electric field at that point and the distance from the point to a reference point.

Now, for a positive charge initially at rest in an electric field, the answer to the question depends on the direction of the electric field. If the field is directed towards the positive charge, then the charge will move in the direction of the field, towards a position with higher potential and lower potential energy (answer b). This is because the charge will experience a force in the direction of the field, and work will be done on the charge, decreasing its potential energy.

If the electric field is directed away from the positive charge, then the charge will move in the opposite direction, towards a position with lower potential and higher potential energy (answer c). In this case, the charge will experience a force opposite to the direction of the field, and work will be done by the charge, increasing its potential energy.

In summary, the movement of a positive charge in an electric field depends on the direction of the field and the relative positions of the charge and the reference point. The concept of potential energy and electric potential can help us understand and predict the movement of the charge in the field.

## What is the difference between potential energy and electric potential?

Potential energy is a measure of the stored energy an object has based on its position or configuration. Electric potential, on the other hand, is a measure of the potential energy per unit charge in an electric field.

## How are potential energy and electric potential related?

The electric potential is directly proportional to the potential energy in an electric field. As the electric potential increases, so does the potential energy.

## What is the unit of measurement for potential energy and electric potential?

Potential energy is measured in joules (J), while electric potential is measured in volts (V).

## Can potential energy and electric potential be negative?

Yes, both potential energy and electric potential can be negative. This indicates that the energy is being released or used up in a system.

## How does an object's charge affect its electric potential?

An object's charge can affect its electric potential by creating an electric field. The electric potential is higher for objects with a higher charge, and lower for objects with a lower charge.

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