Physics Class 11 & 12: Kinematics and Forces

Kinematics (Lectures 1-8)

• Covers vectors, motion, equations of motion, and motion under gravity.

Forces (Lectures 9-12)

• Includes Newton's laws and different types of forces.

Momentum, Collision, and Impulse (Lectures 13-14)

• Discusses momentum, collisions, and impulse.

Work, Power, and Energy (Lectures 15-18)

• Explores work, power, and energy concepts.

Physics Sections (Class 11 & 12)

• Class 11: Mechanics (50%), Waves (20%), and Heat/Thermodynamics (30%)
• Class 12: Electricity & Magnetism (70%), Optics (20%), and Modern Physics (10%)

Types of Motion

• Rectilinear Motion: Motion along a straight line (e.g., light, car on a runway).
• Two-Dimensional Motion: Motion on a plane (e.g., ant on a wall, planets).
• Three-Dimensional Motion: Motion in space (e.g., bird, mosquito).

Types of Motion (Category 2)

• Translational Motion: All points of an object move in the same direction with the same speed (e.g., car).
• Rotational Motion: All points of an object move in different circles around a fixed axis (e.g., rotating wheel, spinning top).

Point vs. Extended Objects

• Point Object: A small object with a negligible size.

• Extended Object: A larger object.

• Circular motion for point objects transforms into rotational motion for extended objects.

• Oscillatory/vibratory motion is a to-and-fro motion around a fixed point (e.g., pendulum, swinging motion, guitar string).

Scalars and Vectors

• Scalars: Described by magnitude only (e.g., mass, volume).
• Vectors: Described by magnitude and direction (e.g., velocity, acceleration).
• Vector addition/subtraction rules are specific and different from scalar operations. Common scalar quantities include mass, volume, distance, time, temperature, speed, work, energy, pressure, and current. Common vector quantities include velocity, acceleration, displacement, force, and momentum.

Vector Representation

• Vectors are represented by arrows, where the length of the arrow represents the magnitude and the direction indicates the vector's direction.

• Magnitude of a vector is represented with symbols like ||A|| or |A|.

• Vectors can be added, subtracted, and multiplied by scalars.

• The addition of vectors in the same or opposite direction and perpendicular direction is explained.

Types of Vectors

• Antiparallel Vectors: Opposite directions.
• Parallel Vectors: Same direction.
• Collinear Vectors: Lie on the same line.
• Equal Vectors: Same magnitude and direction.
• Negative of a Vector: Same magnitude, but opposite direction.
• Unit Vectors: Magnitude of 1.
• Null/Zero Vectors: Magnitude of 0.
• Coplanar Vectors: Lie on the same plane.

Mathematical Operations of Vectors

• Multiplying a vector by a scalar.
• Adding vectors in the same or opposite direction.
• Adding vectors perpendicular to each other using the triangle method.

Further Study

• Students are assigned homework (H.W.) regarding the motion of a Ferris wheel (booklet).