Introduction to Physics by Professor Ramamurti Shankar

Jul 19, 2024

Lecture Notes: Introduction to Physics by Professor Ramamurti Shankar

Course Overview

  • Course Content: Year-long introduction to major ideas in physics
    • From Galileo and Newton to revolutions in relativity and quantum mechanics
  • Target Audience: Very broad, inclusive of various majors and future career paths

Importance of Physics for Diverse Careers

  • Useful to know about fundamental physics, regardless of future profession
    • Examples given: doctors and special relativity/quantum mechanics

Course Structure and Organization

  • Lecture Schedule: Mondays and Wednesdays from 11:30-12:45
  • Course Website: Essential for accessing materials and problem sets
  • Homework: Assigned on Wednesdays, due the following Wednesday
    • Head TA: Mara Daniel; collect and return graded homework
  • Grading Breakdown:
    • Homework: 20%
    • Midterm: 30% (around October 20th)
    • Final: 50%
    • Amnesty Plan: Final exam score can completely determine course grade if higher
  • Teaching Assistants and Discussion Sections:
    • Mark Caprio: Tuesdays 1:00-2:00 PM (Sloane Lab)
    • Steve Furlanetto: Tuesdays 8:00-10:00 PM (Dunham Lab, Room 220)

Tips for Success in the Course

  • Attend lectures and refer to the book
  • Prioritize doing homework - real learning happens in solving problems
    • Collaboration is encouraged
    • Utilize the undergraduate lounge and TAs
  • Avoid disrupting the class
  • Sleep in class is allowed but with restrictions

Calculus Requirement

  • Basic knowledge of differential calculus is essential
  • Understanding of functions, derivatives, and trigonometry is necessary
  • Textbook appendix can serve as a guide for necessary mathematical concepts

Newtonian Mechanics

  • Objective: Predict the future given the present using Newton's laws
  • Key Topics:
    • Kinematics: Description of present (initial conditions)
    • Dynamics: Explanation of changes (forces causing motion)
  • Kinematics: Space (x) vs. Time (t) graphs
  • Important Concepts:
    • Average velocity and acceleration
    • Instantaneous velocity (derivative of position)
    • Instantaneous acceleration (second derivative of position)

Example Problem: Constant Acceleration

  • Scenario: Object thrown upwards from a building
    • Building height: 15 meters
    • Initial velocity: 10 m/s
    • Acceleration due to gravity: -10 m/s² (approximated for simplicity)
  • Formulas:
    • Position: x(t) = x0 + v0 t + 1/2 at²
    • Velocity: v(t) = v0 + at
    • Range formula: v² = v0² + 2a (x - x0)
  • Solution Steps:
    • Determine maximum height: Time when velocity is 0
    • Calculate time to hit the ground: Set position to zero and solve
    • Analyze velocity and other dynamic properties

Methodologies and Mathematical Derivations

  • Use of calculus to derive kinematic equations
  • Application of derivatives and integrals to solve problems
  • Approximations and simplifications
    • Example: Ignoring finer details or using g ≈ 10 m/s² instead of 9.8 m/s² for ease

Final Remarks

  • Importance of understanding foundational physics principles and thinking like a physicist
  • Encouragement to engage actively in learning and problem-solving