Exercises: Electric Potential

Which of the following best distinguishes electric potential $V$ from the electric field $E$?

A positive charge is moved opposite to the direction the electric force pushes it. What happens to its electric potential energy?

The work done by a constant force $F$ over a displacement $d$ is $W = Fd$. Which energy principle directly connects this to electric potential energy?

The electric potential at a distance $r$ from a point charge $q$ is given by $V = kq/r$, where $k = 9.0 \times 10^9\ \text{N·m}^2/\text{C}^2$. What are the SI units of electric potential?

A point charge of $q = +5.0\ \mu\text{C}$ is fixed in space. Calculate the electric potential at a point $r = 0.30\ \text{m}$ from the charge. Use $k = 9.0 \times 10^9\ \text{N·m}^2/\text{C}^2$.

A point charge of $q = -4.0\ \mu\text{C}$ is fixed in space. What is the electric potential at a distance of $r = 0.20\ \text{m}$ from the charge? Use $k = 9.0 \times 10^9\ \text{N·m}^2/\text{C}^2$.

A charge of $q = +2.0\ \mu\text{C}$ is moved through a potential difference of $\Delta V = 500\ \text{V}$ (from low to high potential). How much work is done by an external agent in moving the charge?

A charge of $q = -3.0\ \mu\text{C}$ moves from a point at $V_A = 200\ \text{V}$ to a point at $V_B = 500\ \text{V}$. Calculate the work done by the electric force on this charge.