MCAT physics 2

  1. Thermodynamics, Calories, and Temperature
    Thermodynamics - the study of heat transfer and its effects.

    Calorie (C)- Quantity measure of heat = 103 calories = 4.134 x 103 J

    Temperature (T) - a measure of the KE (heat content) of particles

    Kelvin: the most commonly used temperature unit with 0K = absolute zero

    TK = TC + 273
  2. Three methods of heat transfer
    Conduction - the transfer of energy via molecular collisions

    Convection - the transfer of heat through fluids (gas, liquid or super-critical fluids) by the physical motion of the fluid

    Radiation - the transfer of energy via electromagnetic waves of motion...only form possible of energy transfer in a vacuum.
  3. 1st and 2nd Laws of Thermodynamics
    • 1st Law: The change in internal energy (U) of a system is equal to the heat (Q) transferred into the system, minus the energy lost by the system when it performs work (W).
    • U = Q - W

    Adiabatic Processes: Q = 0 ... W = -U

    Isovolumetric Processes: W = 0 ... Q = U

    Closed Cycles: U = 0 ... Q = W

    2nd Law: The universe always tends towards an increase in entropy

    Entropy: A measure of the dispersion of energy of a system
Card Set
MCAT physics 2