Course Content
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
Class 11th Physics Online Class For 100% Result
About Lesson

Perfect Gas Equation

  • Perfect gas equation is given by PV=μRT,
    • WhereP,V are pressure, volume, T =absolute temperature,μ = number of moles and R =universal gas constant.
    • R= kBNA where kB = Boltzmann constant and NA = Avogadro’s Number
  • This equation tells about the behaviour of gas at a particular situation.
  • If a gas satisfies this equation then the gas is known as Perfect gas or an ideal gas.

Different Forms of Perfect Gas Equation

  1. PV=μRT (i)
  • Where μ (no. of moles) = N/NA where N=no of molecules and NA = Avogadro number(no of molecules in 1 mole of gas).Orμ = M/Mowhere M=mass of sample of gas and Mo = molar mass.
  • PV = (N/NA)RT(putting μ=N/NA in equation(i))
  • By simplifying PV = NkBT
  • PV=NkBT => P = (N/V) kBT => P=nkBT where n(number density) =N/V where N=number of molecules and V=volume.
  • Therefore we get PV=nkBT
  1. Substitute μ = M/Mo in equation(i)
  • PV=(M/Mo) RT => P=(M/V)1/MoRT where
    • ρ(mass density of the gas) = M/V
  • Therefore P=ρRT/Mo

Ideal Gas

  • A gas that satisfies the perfectgas equation exactly at all pressures and temperatures.
  • Ideal gas is atheoretical concept.
  • No real gas is truly ideal.A gas which is ideal is known as real gas.
  • Real gases approach the ideal gas behaviour for low pressures and high temperatures.

Problem:- ( Kinetic Theory Notes )

Estimate the total number of air molecules (inclusive of oxygen, nitrogen, water vapour

and other constituents) in a room of capacity 25.0 m3 at a temperature of 27 °C and 1 atm



Volume of the room, V = 25.0 m3

Temperature of the room, T = 27°C = 300 K

Pressure in the room, P = 1 atm = 1 × 1.013 × 105 Pa

The ideal gas equation relating pressure (P), Volume (V), and absolute temperature (T)

can be written as:



KB is Boltzmann constant = 1.38 × 10–23 m2 kg s–2 K–1

N is the number of air molecules in the room



= 6.11 × 1026 molecules

Therefore, the total number of air molecules in the given room is 6.11 × 1026

Real gases deviation from ideal gas

  • Real gases approach the ideal gas behaviour for low pressures and high temperatures.
  • Ideal gas equation PV=μRT, for 1 mole ,μ=1,PV=RT
  • =>PV/RT=constant
  • Graph should be a straight line(parallel to x-axis) for ideal gas.
  • This means it has constant value at all temperature and all pressure.

But in case of real gases graph approach ideal gas behaviour at high temperature and low pressure.

  • At high temperature and low pressure molecules are far apart. When temperature is increased the molecules will move randomly far from each other.
  • As a result molecular interaction decreases the gas behaves as an ideal gas.
  • The ideal behaviour comes into picture when the molecular present inside the gas don’t interact with each other.

Charles’s law:-Consider If P(Pressure) is constant, then

Kinetic Theory Notes
Wisdom TechSavvy Academy