Electrical Potential Energy and Potential

In summary, an electron that accelerates from a point near a collection of negative source charges towards a point near a collection of positive source charges experiences a decrease in electric potential energy as it moves towards a region of higher electric potential. This is because the electric potential, represented by V, increases as the electron moves towards the positive source, while the charge, represented by q, remains negative. Therefore, the equation U=qV shows that the potential energy, U, decreases as v increases.
  • #1
and

Homework Statement


An electron that accelerates from a point near a collection of negative source charges toward a point near a collection of positive source charges experiences

A) a decrease in electric potential energy as it moves toward a region at a lower electric potential
B) a decrease in electric potential energy as it moves toward a region at a higher electric potential
C) an increase in electrical potential energy as it moves toward a region at a lower electric potential
D) an increase in electrical potential energy as it moves toward a region at a higher electric potential
E) no change in electrical potential energy

The answer is suppose to be B

Homework Equations


U = qV
V = kQ/r
Force (electro static) x d = U

The Attempt at a Solution


Please correct me if I said something incorrectly
From what I understand, Negative source has lower electric potential, and Positive source has higher electric potential. Because the question asks about an electron, it is obvious that it moves towards region of higher electric potential, aka the positive source.

However, this is the part that doesn't really make sense to me. I KNOW that the electric potential will decrease because the U (potential energy) is decreasing as it goes from negative to positive source, just like how gravitational potential decreases.

But if you think about it, because electric potential is getting higher, shouldn't U get higher, according to the equation U=qv? The equations don't make sense to me... please help!
Thanks.

-Andrew
 
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  • #2
and said:
because electric potential is getting higher, shouldn't U get higher, according to the equation U=qv??
But q is negative here, so increasing v means decreasing U.
 
  • #3
Oh, you are right haha. Thanks for the clarification
 

FAQ: Electrical Potential Energy and Potential

What is electrical potential energy?

Electrical potential energy is the energy that a charged particle possesses due to its position in an electric field. It is the potential to do work based on the interaction between electric charges.

How is electrical potential energy different from electrical potential?

Electrical potential energy is a scalar quantity that represents the potential of a charged particle to do work. Electrical potential, on the other hand, is a vector quantity that represents the electric potential at a specific point in space.

What is the unit of electrical potential energy?

The unit of electrical potential energy is the joule (J). However, in some cases, it may also be expressed in electron volts (eV) or kilowatt-hours (kWh).

What factors affect the electrical potential energy of a system?

The electrical potential energy of a system is affected by the magnitude of the charges involved, the distance between them, and the medium in which they are located. It is also affected by the direction of the electric field and the orientation of the charges.

Can electrical potential energy be converted into other forms of energy?

Yes, electrical potential energy can be converted into other forms of energy such as kinetic energy, thermal energy, or light energy. This conversion occurs when the charged particles move in response to the electric field and do work.

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