Course Content
Class 11 Physics Chapter 1 Physical World
Section Name Topic Name 1 Physical World 1.1 What is physics? 1.2 Scope and excitement of physics 1.3 Physics, technology and society 1.4 Fundamental forces in nature 1.5 Nature of physical laws
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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Conservative & Non-Conservative Forces

  • Conservative forces are those for which work done depends only on initial and final points.
    Example- Gravitational force, Electrostatic force.
  • Non-Conservative forces are those where the work done or the kinetic energy did depend on other factors such as the velocity or the particular path taken by the object.
    Example- Frictional force.
Class 11 Physics Work Energy Power Notes
Work Energy Power

The Conservation of Mechanical Energy

  • Mechanical Energy is the energy associated with the motion and position of an object.
  • The quantity K +V(x), is called the total mechanical energy of the system.
  • For a conservative force, ΔK = ΔW = F(x) Δx
    Also, – V(x) = F(x) Δx
  • This employs Δ(K+V) =0 for a conservative force.
  • Individually the kinetic energy K and the potential energy V(x) may vary from point to point, but the sum is a constant.
  • Conservative Force:
  • A force F(x) is conservative if it can be derived from a scalar quantity V(x) by the relation  : F(x) = – dv/dx
  • The work done by the conservative force depends only on the end points.
  • A third definition states that the work done by this force in a closed path is zero.
  • The total mechanical energy of a system is conserved if the forces, doing work on it, are conservative.
Class 11 Physics Work Energy Power Notes

Potential energy of spring

  • The spring force is an example of a variable force, which is conservative.
  • In an ideal spring, Fs = − kx , this force law for the spring is called Hooke’s law.
  • The constant k is called the spring constant. Its unit is N m-1.
  • The spring is said to be stiff if k is large and soft if k is small.
Class 11 Physics Work Energy Power Notes
Work Energy Power
  • Spring force is position dependent as first stated by Hooke, (Fs = − kx)
  • Work done by spring force only depends on the initial and final positions. Thus, the spring force is a conservative force.
  • We define the potential energy V(x) of the spring to be zero when block and spring system is in the equilibrium position.
  • For an extension (or compression) x,  V(x) = kx2/2

If the block of mass m is extended to xm and released from rest, then its total mechanical energy at any arbitrary point x (where x lies between – xm and + xm) will be given by:

Class 11 Physics Work Energy Power Notes
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