Chapter 4: Electrostatics: Energy and Potential

Quiz

1. An electron ( C) leaves the cathode of a cathode ray tube (CRT) and travels in a uniform electrostatic field toward the anode, which is at a potential  V with respect to the cathode. What is the work W done by the electrostatic field involved in moving the electron from the cathode to the anode?

, kJ

, J

, J

, J



2. In Problem #1, what is the electric field strength  if the distance between the cathode and the anode is 10 cm?

, V/m

, V/m

, V/m

, kV/m



3. The electrostatic potential due to a point charge  at a distance  cm away from it is  V. What is the potential  of a charge  at a distance  cm from it?

, V

, V

, V

, V



4. The electrostatic potential due to a dipole , at a distance  cm away from it along the z-axis, is  V. What is the potential  of a dipole   at a distance  cm from it along the z-axis?

, V

, V

, V

, V



5. The electrostatic potential

, V

where x is measured in meters and  is the permittivity of vacuum, exists in a region of space (vacuum) in the shape of a parallelogram of size  cm. What is the electrostatic energy  stored in this region?

, J

, J

, J

, J