Thermodynamics — Class 12 Maharashtra HSC Physics revision notes
A 6-page visual revision sheet for Thermodynamics, written for Class 12 Maharashtra HSC Physics. Formulas, diagrams and the traps that cost marks, laid out to be read the night before rather than the term before. Free, and it opens inside CapCompass.
Page 1 as PDF
Thermodynamics in one look
the system, the four named processes and the two engines built out of them
System, surroundings and equilibrium
- a system is what's under study, everything else the surroundings, split by a boundary
- intensive variables (P, T, density) don't change with size; extensive ones (mass, U) do
- equilibrium needs three at once: mechanical, thermal, chemical
- internal energy is a state function: set by the state, never the route taken
Zeroth law of thermodynamics
- bodies in contact exchange heat until their temperatures are equal
- A in thermal equilibrium with C, and B with C: then A with B too
- the shared quantity is temperature: every thermometer relies on this law
- named after the first and second laws, yet logically it comes first
Heat, work and the sign convention
- Q and W are not state functions: they change with the path taken
- sign convention: Q positive when absorbed, W positive when done by the system
- internal energy of an ideal gas is set by its temperature alone
The first law of thermodynamics
- general statement
Δ U = Q - W - a complete cycle, back to the start
Δ U = 0,quad Q = W - no heat crosses the boundary (adiabatic)
Q = 0,quad Δ U = -W
Page 1 of 6. The full sheet, all 6 pages, opens free in the app.
What this Thermodynamics sheet covers
- thermodynamic system
- System, surroundings and equilibrium
- zeroth law
- Zeroth law of thermodynamics
- Heat, work and the sign convention
- The first law of thermodynamics
- general statement
- a complete cycle, back to the start
- no heat crosses the boundary (adiabatic)
- Work as the area under the p-V curve
- work for an infinitesimal volume change
- total work between two states
- constant pressure (isobaric), the simplest case
- adiabatic process
- isothermal process
- Isothermal and adiabatic, the equations
- isothermal, ideal gas
- work done, isothermal
- adiabatic, ideal gas
- work done, adiabatic
- Isothermal vs adiabatic: the limits
- Isochoric process and the cyclic process
- isochoric, volume fixed
- cyclic, back to the start
- Two specific heats, and why they differ
- Free expansion
- Reversible and irreversible processes
- Reversible process
- Irreversible process
- heat engine
- net heat absorbed per cycle
- net work done per cycle
- thermal efficiency
- refrigerator
- coefficient of performance
- Refrigerator, air conditioner and heat pump
- typical household refrigerator
- typical room air conditioner
- second law
- Second law of thermodynamics
- carnot
- Carnot cycle
- Carnot engine and Carnot refrigerator
- Carnot efficiency, source T_H, sink T_C
- temperatures measured in
- Carnot refrigerator, coefficient of performance
- Entropy and the direction of change
- Traps that cost marks
- Tricks that save time
How CapCompass uses this sheet
These notes are not a standalone PDF. CapCompass plans Physics chapter by chapter against your real exam dates and free hours, and when the plan reaches Thermodynamics the sheet opens inside the study block itself — at the page covering the sub-topic that block is on, with the timer still running. Revision arrives at the moment the plan says revise, instead of having to be gone looking for.
More Physics Class 12 revision notes
- AC Circuits
- Current Electricity
- Dual Nature of Radiation and Matter
- Electromagnetic Induction
- Electrostatics
- Kinetic Theory of Gases and Radiation
- Magnetic Fields due to Electric Current
- Magnetic Materials
- Mechanical Properties of Fluids
- Oscillations
- Rotational Dynamics
- Semiconductor Devices
- Structure of Atoms and Nuclei
- Superposition of Waves
- Wave Optics