Chapter 4 of Class 11 Physics extends 1D motion to 2D. Motion in a plane requires vectors and covers key topics like projectile motion and uniform circular motion.
In projectile motion, horizontal velocity remains constant (no air resistance), while vertical velocity changes due to gravity. These two components are completely independent.
Vector Addition — Triangle Law: If two vectors are placed head to tail, the resultant is the vector from the tail of the first to the head of the second.
When an object is thrown at an angle and moves under gravity alone — that is projectile motion.
Key formulas (initial velocity u at angle θ):
Motion in a circle with constant speed.
The horizontal range is maximum at **θ = 45°**. At this angle, sin2θ = sin90° = 1, giving R = u²/g (maximum possible range).
What is a Dry Cell? Structure and Working
Learn what a dry cell is. Discover the internal structure, including the carbon rod and zinc casing, and how it uses chemical paste to generate electricity.
Efficiency Formula in Physics
Learn the formula for Efficiency in physics. Understand the ratio of useful work output to total energy input, and why no machine is 100% efficient.
Einstein's Photoelectric Equation Explained
Learn Einstein's Photoelectric Equation in detail. Understand the formula KE = hν - φ, the concept of work function, threshold frequency, and how it proved the particle nature of light.
Electric Bell: Diagram and Working Principle
Learn how an electric bell works. Understand the circuit diagram, the role of the electromagnet, the armature, and the hammer in creating the ringing sound.
What is an Electric Cell?
Learn what an electric cell is. Understand the definition, how a chemical cell converts chemical energy to electrical energy, its components, and types.
Turn this guide into revision flashcards, a practice exam, or an AI-generated podcast — free, no signup required.