Physics Quicksheets - Thermodynamics

Linear Expansion: the increase in length by most solids when heated. 

mnemonic: "a Lot" 




Volume Expansion: the increase in volume of fluids when heated.

Conduction: the direct transfer of energy via molecular collisions

Convection: the transfer of heat by the physical motion of the heated material (only liquids and gases)

Radiation: the transfer of energy by electromagnetic waves.

mnemonic: looks like MCAT

Can only be used to find Q when the object does no change phase

• Q>0 means heat is gained
• Q<0 means heat is lost

Heat of Transformation: the quantity of heat required to change the phase of 1kg of a substance.

Q = mL 


(phase changes are isothermal processes)

*When the piston expands, work is done by the system (W>0)


*When the piston compresses the gas, work is done on the system (W<0).


*The area under a P vs V curve is the amount of work done in a system.

Second Law of Thermodynamics: in any thermodynamic process that moves from one state of equilibrium to another, the entropy of the system and environment together will either increase or remain unchanged.