Ph-204 Chap 21

The flashcards below were created by user Allistermark on FreezingBlue Flashcards.

  1. The electric potential V is:
    created by charges and exists at every point surrounding those charges.
  2. When a charge q is brought near these charges:
    • it acquires an electric potential energy
    • Uelec = qV 
    • at a point where the other charges have created an electric potential V.
  3. Energy is conserved for a charged particle in an electric potential:
    • Kf + qVf = Ki + qVi
    • or
    • ΔK = -qΔV
  4. Potential differences ΔV are created by a separation of charge. Two important sources of potential difference are:
    • 1.A battery, which uses chemical means to separate charge and produce a potential difference.  
    • 2.The opposite charges on the plates of a capacitor, which create a potential difference between the plates.
  5. The electrical potential of a point charge q is:
  6. For a conductor in electrostatic equilibrium
    • 1.Any excess charge is on the surface. 
    • 2.The electric field inside is zero. 
    • 3.The exterior electric field is perpendicular to the surface. 
    • 4.The field strength is largest at sharp corners. 
    • 5.The entire conductor is at the same potential and so the surface is an equipotential.
  7. What is C:
  8. The potential difference ΔVC between two conductors charged to ±Q is proportional to the charge:
    • ΔVC = Q/C 
    • where C is the capacitance of the two conductors.
  9. The permittivity constant or εο:
  10. A parallel-plate capacitor with plates of area A and separation d has a capacitance:
    C = κεοA/d
  11. When a dielectric is inserted between the plates of a capacitor, it's capacitance is:
    Increased by a factor κ, the dielectric constant of the material.
  12. 1.The energy stored in a capacitor is:
    2.This energy is stored in the electric field, which has energy density:
    • 1.UC= ½C(ΔVC)2 
    • 2.UE=½κεοE2
  13. For a capacitor charged to ΔVC the potential at distance x from the negative plate is:
    • V=x/dΔVC 
    • The electric field inside is: 
    • E=ΔVC/d
  14. Electric potential:
    1V = 1J/C
  15. Electric field:
    1V/m=1 N/C
  16. Energy:
    1 electron volt = 1eV = 1.60x10-19 J is the kinetic energy gained by an electron upon accelerating through a potential difference of 1V.
Card Set:
Ph-204 Chap 21
2013-02-17 04:30:14
Chapter 21 Electric Potential Energy

Electric Potential Energy and Electric Potential,
Show Answers: