555D AP Physics C: Unit 3B Electric Potential

The successful student will be able to:

• Understand the concept of electric potential so they can:
  • Calculate how much work is required to move a test charge from one location to another in the field of fixed point charges (APCIIIA2b5) (Knight 28.2 )
  • Calculate the electrostatic potential energy of a system of two or more point charges, and calculate how much work is required to establish the charge system (APCIIIA2b6) (Knight 28.2)
  • Calculate the electrical work done on a charge or use conservation of energy to determine the speed of a charge that moves through a specified potential difference (APCIIIA2b2) (Knight 28.5)
  • Calculate the potential difference between two points in a uniform electric field and state which point is at the higher potential (APCIIIA2b4) (Knight 28.5)
  • Determine the electric potential in the vicinity of one or more point charges (APCIIIA2b1) (Knight 28.6, 28.7)
  • Determine the direction and approximate magnitude of the electric field at various positions given a sketch of equipotentials (APCIIIA2b3) (Knight 29.1, 29.3)
  • Use integration to determine electric potential difference between two points on a line, given electric field strength as a function of position along that line. (APCIIIA2b7) (Knight 29.1, 29.2)
  • State the general relationship between field and potential, and define and apply the concept of a conservative electric field (APCIIIA2b8) (Knight 29.1, 29,3)
• Understand the physics of the parallel-plate capacitor, so they can:
  • Describe the electric field inside the capacitor, and relate the strength of this field to the potential difference between the plates and the plate separation. (IIIB2b1) (Knight 26.5, 28.5)
• Students should be able to describe and sketch a graph of the potential inside and outside a charged conducting sphere. (APCIIIB1b) (Knight 28.6, 29.3, 29.4)
• Know the fields of highly symmetric charge distributions so they can derive expressions for electric potential as a function of position in the cases of oppositely charged parallel plates, a long, uniformly-charged wire, or thing cylindrical or spherical shell (APCIIIA4b4) (Knight 28.5, 28.6, 28.7)

Due date Day Assignment

3/7 Fri Read/Scan/Use: Knight 28, 29,1à29.4

3/11 Tue Do: Chapter 28: 2, 6, 10, 13, 19, 20, 24, 27, 30, 42, 58, 67, 68,

69, 74

3/12 Wed Do: Chapter 29: 4, 11 (offline only), 15, 36, 39, 79

Lab 3: Electrostatic potential and the Electric field

3/13 Thu Test: Gauss’s Law and Electrostatic potential

Links

• MIT's OpenCourseware presents Walter Lewin's videos for 8.02, the freshman electricity and magnetism class. MIT's equivalent of AP Physics C: Electricity and Magnetism.
  • Lecture 4: Electrostatic Potential and Electric Energy
  • Lecture 5: Electrotatic Shielding (Faraday Cage)
• Prentice Hall's web page on Giancoli Chapter 17 Electric Potential and Electric Energy; Capacitance (no calculus)
• Haliday, Resnick and Walker's page on Chapter 25 - Electric Potential (Calculus based)
• Between 1799 and 1800, Count Alessandro Volta (1745-1827)invented the voltaic pile, essentially a series of capacitors, which was the forerunner of the modern electric battery. Another article on Volta can be found at The Catholic Encyclopedia, with yet another at The Idea Factory