Physics Flashcards - DC and AC Circuits

  1. (T/F) In DC current, the charge flows in one direction only.
    True.
  2. (T/F) In AC current, the charge flows in one direction only.
    False, in AC current, the flow of charge changes direction periodically.
  3. (T/F) By convection, the direction of current is the direction in which a negative charge would flow.
    False, the direction of current is the direction in which a positive charge would flow.
  4. What is the formula for Ohm's Law? 

    V =
    Volts = (current)(resistance) = iR
  5. How do the following affect the resistance of a conductor? 

    1. Increased length

    2. Increased cross-sectional area

    3. Increased temperature

    4. Increased resistivity (ρ)
    1. As length increases, so does resistance.

    2. As cross-sectional area increases, resistance decreases.

    3. As temperature increases, resistance typically increases.

    4. As resistivity increases so does resistance.
  6. What is the formula for electrical power? 

    P =
    P = (current)(voltage) = iV = i2R = V2/R
  7. What is the formula for calculating resistance given resistors in series?

    Rs =
    Rs = R1 + R2 + R3 + ....+ Rn
  8. What is the formula for calculating resistance given resistors in parallel?

    Rp =
    Image Upload 2
  9. What is Kirchoff's 2nd Law?
    Kirchoff's 2nd Law states that the sum of the voltage drops around a circuit loop equals the sum of the voltage rises around the loop.
  10. If 7A of current flow into a three way junction and 3A leave via one of the routes, how much current leaves via the other?
    7A - 3A = 4A
  11. What is the formula for capacitance? 

    C =
    Image Upload 4
  12. What are the units of capacitance?
    The units of capacitance are Farads.

    1 Farad = 1 Coulomb/Volt
  13. What is the formula for the electric field between the plates of a capacitor?

    E =
    Image Upload 6
  14. (T/F) As plate area increases, capacitance increases proportionally.
    True.
  15. Does the introduction of a dielectric material between the plates of a capacitor increase or decrease the capacitance?
    A dielectric material increases the capacitance. 

    The new capacitance (C') = CK, where K = dielectric constant.
  16. What is the formula for calculating capacitance given capacitors in series?

    Cs =
    Image Upload 8
  17. What is the formula for calculating capacitance given capacitors in parallel?

    Cp =
    Cp = C1 + C2 + C3+ ... + Cn
  18. For AC current, what is the formula for calculating Irms?
    Image Upload 10
  19. For AC current, what is the formula for calculating Vrms?
    Image Upload 12
Author
awc1990
ID
212587
Card Set
Physics Flashcards - DC and AC Circuits
Description
Physics Flashcards - DC and AC Circuits Kaplan MCAT P42-P47
Updated