## Syllabus for IGNOU BSc Physics - Elementary Mechanics BPHE-101

We live in a Universe of continual motion. Electrons swarming around atoms in matter, buses speeding along highways, planets orbiting the sun, the stars and galaxies rushing apart are all examples of matter in motion.

The branch of physics dealing with the motion of bodies as well as bodies at rest or in equilibrium is called mechanics. Since motion is such an important feature of the world around us, it is the logical subject to begin the study of physical phenomena. Therefore, we are offering this course entitled Elementary Mechanics as the first elective in physics. As the title suggests, in this course you will study elementary concepts and laws of mechanics, including the laws or conservation of linear momentum, angular momentum and energy.

We use the concepts and laws of mechanics constantly in everyday life and in engineering applications. We use them when we ride bicycles, lift heavy loads, play tennis or construct bridges. Many fascinating developments of the space age, such as launching of space probes and artificial satellites, are direct applications of the laws of mechanics. These laws allow us to predict with remarkable accuracy the motion of planets in the solar system as well as to explain the formation of stars and galaxies. Syllabus for IGNOU BSc Physics - Elementary Mechanics BPHE-101 facilitate study the applications of these concepts and laws of simple and familiar physical situations in Blocks 1 and 2 of this course. Their applications to more complex situations, such as planetary motion, many - particle systems, rigid body dynamics and motion in non-inertial frames of reference form the subject of Block 3.

Mechanics is the most fundamental area of physics. A sound knowledge of mechanics is needed to study vibrations and waves, electromagnetism, thermal physics, quantum mechanics, special and general theories of relativety, etc. To study physics at the undergraduate level, this course is a must.

## Syllabus Per Block Divisions in IGNOU BSc Physics - Elementary Mechanics BPHE-101

### Block 1: Revising Particle Kinematics and Dynamics

**Unit 1**: Motion: An Introduction**Unit 2:**Motion in a Straight Line**Unit 3:**Motion in a Plane**Unit 4:**Newton’s Laws of Motion and Force**Unit 5**: Applying Newton’s Laws**Unit 6:**Linear Momentum and Impulse**Appendix 1**: Vector Algebra**Appendix 2:**Basic Concepts of Calculus

### Block 2: Work, Energy and Angular Motion

**Unit 7:**Work and Kinetic Energy**Unit 8:**Conservation of Energy and Potential Energy**Unit 9:**Angular Motion of a Particle**Unit 10:**Torque and Angular Momentum**Appendix:**Scalar and Vector Products of Two Vectors

### Block 3: Systems of Many Particles

**Unit 11**: Motion under Central Forces**Unit 12:**Dynamics of Many-particle Systems**Unit 13:**Conservation Laws for Many-particle Systems**Unit 14:**Rigid Body Dynamics**Unit 15:**Motion in Non-inertial Frames of Reference**Appendix 1**: Conic Sections**Appendix 2:**Moment of Inertia of Rigid Bodies

## Detailed Syllabus for IGNOU BSc Physics - Elementary Mechanics BPHE-101

### Kinematics of Motion:

Displacement, Velocity and Acceleration; Uniform Circular Motion, Relative Motion.

### Dynamics of Motion:

Force, Newton's Laws of Motion, Law of Gravitation; Principle of Superposition; Applications of Newton's Laws; Equilibrium of Forces; Linear Momentum, Conservation of Linear Momentum; Impulse; Motion with Variable Mass, Rocket Motion; Gravity and its Variation, Velocity of Escape; Fundamental Forces in Nature.

### Work and Energy:

Work done by a Constant Force, and a Variable Force; Kinetic Energy and Work-Energy Theorem, Potential Energy and Conservative Forces, Principle of Conservation of Energy, Energy Diagrams; Elastic and Inelastic Collisions; Power.

### Angular Motion:

Kinematics of Angular Motion: Angular Displacement, Angular Velocity and Angular Acceleration, Use of Plane Polar Coordinates for describing Circular Motion and General Angular Motion, Relations between Linear and Angular Kinematical Variables; Dynamics of Angular Motion; Torque, Kinetic Energy of Rotation; Angular Momentum, Conservation of Angular Momentum and its Applications.

### Many Particle Systems:

Central Conservative Forces: Properties of Motion under Central Conservative Forces; Inverse Square Central Conservative Forces; Inverse square Gravitational Force; Motion of Two-Body Systems, Equation of Motion in Centre-of-mass and Relative Coordinates, Linear and Angular Momentum and Kinetic Energy.

### Dynamics of Many-Particle Systems:

Linear Momentum, Angular Momentum and Kinetic Energy of an N-particle System.

### Rigid Body Dynamics:

Translational, Rotational and General Motion of a Rigid Body; Moment of Inertia; Rotational Dynamics of a Rigid Body, Rotational Analogue of Newton's Second Law, Work and Energy in Rotational Motion; Gravitational Potential Energy due to Earth as a Solid Sphere; Conservation of Angular Momentum and its Applications, Precession.

### Non-Inertial Frames of Reference:

Motion Observed from a Non-Inertial Frame, Newton's Second Law and Inertial Forces, Weightlessness; Rotating Frame of Reference: Centrifugal Force, Coriolis Force; The Earth as a Rotating Frame of Reference, Variation of g with Latitude, Motion on the Rotating Earth, Foucault's Pendulum. (Qualitative discussion only)

### Appendixes:

Vector Algebra, Vectors in One, Two and Three Dimensions, Vector Addition; Calculus, Concept of Derivative and Integral; Products of Vectors; Conic Sections; Moment of Inertia.