Electric Potential Energy and Work

What does the potential energy of a system of charges represent?

• The total kinetic energy of the charges.

• The work done to bring the charges from infinity to their current positions.

• The force exerted between the charges.

• The amount of heat generated by the charges.

When assembling a system of charges, how does the total work done relate to the path taken to bring the charges together?

• It depends on the specific path chosen for each charge.

• It is always zero regardless of the path.

• It is independent of the path taken.

• It is maximized by taking the shortest path.

When bringing the first charge from infinity into an empty space, what is the work done?

• Positive, because energy is required to move the charge.

• Negative, because the charge is attracted to the empty space.

• Zero, because there are no other charges to exert a force.

• Dependent on the path taken by the charge.

When bringing a second charge from infinity into a system where a first charge is already present, why is work done?

• The second charge gains kinetic energy.

• The first charge attracts or repels the second charge.

• The second charge creates its own electric field.

• The distance between the charges changes.

What does electric potential at a point represent?

• The force exerted on a unit charge at that point.

• The work done to move a unit positive charge from infinity to that point.

• The total energy stored in the electric field.

• The rate at which charge flows through that point.

If the electric potential at a point is V, how much work is required to bring a charge Q from infinity to that point?

• V/Q

• Q/V

• V * Q

• V + Q

What is the total electric potential energy (U) of a system consisting of three point charges q1, q2, and q3, with distances r12, r13, and r23 between them, respectively? (k is Coulomb's constant)

• U = k(q1q2/r12 + q1q3/r13 + q2q3/r23)

• U = k(q1q2/r12 + q1q3/r13 - q2q3/r23)

• U = k(q1q2/r12 * q1q3/r13 * q2q3/r23)

• U = k(q1+q2+q3)/(r12+r13+r23)

How is the total potential energy of a system of multiple charges generally calculated?

• By summing the potential energies of each individual charge.

• By summing the potential energies of all possible pairs of charges.

• By multiplying the potential energies of all charges.

• By taking the average of the potential energies of all charges.