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Class 11 Physics Chapter 4 Motion In A Plane
4 Motion in a plane 4.1 Introduction 4.2 Scalars and vectors 4.3 Multiplication of vectors by real numbers 4.4 Addition and subtraction of vectors – graphical method 4.5 Resolution of vectors 4.6 Vector addition – analytical method 4.7 Motion in a plane 4.8 Motion in a plane with constant acceleration 4.9 Relative velocity in two dimensions 4.10 Projectile motion 4.11 Uniform circular motion
Class 11 Physics Chapter 5 Laws of motion
Section Name Topic Name 5 Laws of motion 5.1 Introduction 5.2 Aristotle’s fallacy 5.3 The law of inertia 5.4 Newton’s first law of motion 5.5 Newton’s second law of motion 5.6 Newton’s third law of motion 5.7 Conservation of momentum 5.8 Equilibrium of a particle 5.9 Common forces in mechanics 5.10 Circular motion 5.11 Solving problems in mechanics
Class 11 Physics Chapter 6 Work Energy and Power
Section Name Topic Name 6 Work Energy and power 6.1 Introduction 6.2 Notions of work and kinetic energy : The work-energy theorem 6.3 Work 6.4 Kinetic energy 6.5 Work done by a variable force 6.6 The work-energy theorem for a variable force 6.7 The concept of potential energy 6.8 The conservation of mechanical energy 6.9 The potential energy of a spring 6.10 Various forms of energy : the law of conservation of energy 6.11 Power 6.12 Collisions
Class 11 Physics Chapter 7 Rotation motion
Topics Introduction Centre of mass Motion of COM Linear Momentum of System of Particles Vector Product Angular velocity Torque & Angular Momentum Conservation of Angular Momentum Equilibrium of Rigid Body Centre of Gravity Moment of Inertia Theorem of perpendicular axis Theorem of parallel axis Moment of Inertia of Objects Kinematics of Rotational Motion about a Fixed Axis Dynamics of Rotational Motion about a Fixed Axis Angular Momentum In Case of Rotation about a Fixed Axis Rolling motion
Class 11 Physics Chapter 9 mechanics properties of solid
Section Name Topic Name 9 Mechanical Properties Of Solids 9.1 Introduction 9.2 Elastic behaviour of solids 9.3 Stress and strain 9.4 Hooke’s law 9.5 Stress-strain curve 9.6 Elastic moduli 9.7 Applications of elastic behaviour of materials
Class 11 Physics Chapter 11 Thermal Properties of matter
Section Name Topic Name 11 Thermal Properties of matter 11.1 Introduction 11.2 Temperature and heat 11.3 Measurement of temperature 11.4 Ideal-gas equation and absolute temperature 11.5 Thermal expansion 11.6 Specific heat capacity 11.7 Calorimetry 11.8 Change of state 11.9 Heat transfer 11.10 Newton’s law of cooling
Class 11 Physics Chapter 14 Oscillations
Section Name Topic Name 14 Oscillations 14.1 Introduction 14.2 Periodic and oscilatory motions 14.3 Simple harmonic motion 14.4 Simple harmonic motion and uniform circular motion 14.5 Velocity and acceleration in simple harmonic motion 14.6 Force law for simple harmonic motion 14.7 Energy in simple harmonic motion 14.8 Some systems executing Simple Harmonic Motion 14.9 Damped simple harmonic motion 14.10 Forced oscillations and resonance
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Class 11 Physics Chapter 12 Thermodynamics Notes and NCERT Solution

Coefficient of Performance (COP) of the refrigerator

  • It is denoted by α.
  • Mathematically given as :
    • α = Q2/W
    • where Q2 is the heat extracted from the cold reservoir
    • W is the work done on the system–the refrigerant
  • α can be greater than 1
  • Using Law of energy conservation :- Q2+W=Q1
  • This implies W=Q2-Q1
  • Therefore:-
  • α =Q2/Q1-Q2
  • W ≠ 0 then Q1-Q2 ≠0
  • This implies α ≠infinite
Class 11 Physics Chapter 12 Thermodynamics Notes and NCERT Solution
Thermodynamics Notes

Second law of Thermodynamics

There are 2 statements of second law of thermodynamics given by two scientists:

  • Kelvin-Planck ∫Statement: – No process is possible whose result is the absorption of heat from a reservoir and the complete conversion of the heat into work.
  • Clausius statement: – No process is possible whose result is the transfer of heat from a colder object to a hotter object.

Explanation of Kelvin-Planck Statement: It is always impossible that the total amount of heat which is supplied to system will get converted to work, and there will always be loss of heat. Complete conversion of heat into work is not possible.

Explanation of Clausius statement: – Transfer of heat from colder body to hotter body won’t take place until some external work is done on the system.

Reversible and Irreversible processes

Reversible Process

  • A thermodynamic process is reversible if the process can be turned back such that the system and surroundings return to their original states, with no other change anywhere else in the universe.
  • This means in the Reversible processes if a process starts from initial state then it goes to final state and then it can reversed back from final state to initial state.
  • Examples:- Isothermal expansion and compression,  Electrolysis 
  • A process is reversible if :-
  1. It is quasi-static
  2. No dissipative forces (that is no loss of heat by friction etc.).
  3. Both initial and final states of the system are in thermodynamic equilibrium with each other.

Irreversible Process

  • Irreversible processes are those that cannot be reversed.
  • Two causes which give rise to irreversible processes
    • Irreversible processes takes place at a very fast rate.
    • Dissipative Effects.
  • Examples:-Plastic deformation, Combustion, Diffusion, Falling of water from hill.

Carnot engine

  • A Carnot engine is named after Carnot scientist.
  • It is a reversible heat engine operating between two temperatures.
  • It has a maximum efficiency which no other engine can have.

Cycle of processes in a Carnot engine

Basic Function of any heat engine is it will take heat Q1 from a hot reservoir at temperature T1 and give heat Q  to a cold reservoir at temperature T2.

  • As system is absorbing heat so it is isothermal expansion. Engine absorbs heat Q1 at temperature T1.
  • An adiabatic process takes place inside the engine because of which there is increase in the temperature of the engine from T1 to T2 but no flow of heat.
  • As system is releasing heat so it is isothermal contraction. Engine releases heat Q2 at temperature T2.
  • An adiabatic process takes place again which changes the temperature of the system from T2 to T1.
  • One cycle of Carnot engine will have Isothermal expansion then adiabatic process, and then isothermal contraction followed by adiabatic process.
  • This will keep on repeating.

The efficiency of Carnot engine is given by:-

η = 1 – T2/T1

The graph below depicts the Carnot cycle for a heat engine with an ideal gas as the working substance.

Class 11 Physics Chapter 12 Thermodynamics Notes and NCERT Solution
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