AP Physics C: Electricity and Magnetism Flashcards: Electric Potential Energy
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Review key ideas with interactive flashcards. This set includes 10 cards to help you master important concepts.
Describe the electric potential energy of a system of charges.
It is the total energy stored within the system due to the electrostatic interactions between all pairs of charges that make up the system.
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Describe the electric potential energy of a system of charges.
It is the total energy stored within the system due to the electrostatic interactions between all pairs of charges that make up the system.
If a positive charge and a negative charge are moved farther apart, what happens to the electric potential energy of the system?
The potential energy becomes less negative (it increases towards zero) because work must be done against the attractive force to separate them.
What is the electric potential energy of a system of two charges that are infinitely far apart?
The electric potential energy is defined as zero when the charges are infinitely separated (as r approaches infinity).
A system consists of three charges: A, B, and C. How many individual interactions must be calculated to find the total electric potential energy?
You must calculate the sum of the electric potential energies for the three unique pairs: (A, B), (A, C), and (B, C).
What does the variable 'r' represent in the electric potential energy equation, $U_{E}=k\frac{q_{1}q_{2}}{r}$?
The variable 'r' represents the distance separating the centers of the two charged objects, $q_1$ and $q_2$.
How is the total electric potential energy of a system with multiple charged objects calculated?
The total electric potential energy is found by calculating the potential energy for each pair of charges in the system and then summing these individual energies.
If two positive charges are moved closer together, what happens to the electric potential energy of the system?
The electric potential energy of the system increases because work must be done against the repulsive force to bring them closer.
What is the relationship between the signs of two interacting charges and the sign of their electric potential energy?
Like charges (both positive or both negative) result in a positive potential energy, while opposite charges result in a negative potential energy.
How does the electric potential energy between two charges change if the distance 'r' between them is doubled?
Since potential energy is inversely proportional to distance ($U_E \propto 1/r$), doubling the distance will cause the potential energy to be halved.
What is the general equation for the electric potential energy ($U_E$) between two charged objects?
The equation is $U_{E}=k\frac{q_{1}q_{2}}{r}$, where k is Coulomb's constant, $q_1$ and $q_2$ are the charges, and r is the distance between them.