1st PU Physics Study Notes

1st PU Physics Study Notes

Basic Concepts

• Physics Definition: The study of matter, energy, and their interactions.
• Units: Standard units (SI) used are meter (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol), and candela (cd).

Mechanics

• Kinematics: Study of motion without considering forces.

  • Displacement: Change in position.
  • Velocity: Rate of change of displacement.
  • Acceleration: Rate of change of velocity.
  • Equations of Motion:
    1. ( v = u + at )
    2. ( s = ut + \frac{1}{2}at^2 )
    3. ( v^2 = u^2 + 2as )

• Dynamics: Study of forces and their effects on motion.

  • Newton's Laws of Motion:
    1. First Law (Inertia): An object at rest stays at rest unless acted upon.
    2. Second Law: ( F = ma ) (Force equals mass times acceleration).
    3. Third Law: For every action, there is an equal and opposite reaction.

Work, Energy, and Power

• Work: ( W = F \cdot d \cdot \cos(\theta) )
• Energy: The capacity to do work.
  • Kinetic Energy: ( KE = \frac{1}{2}mv^2 )
  • Potential Energy: ( PE = mgh )
• Power: Rate of doing work; ( P = \frac{W}{t} )

Properties of Matter

• Density: Mass per unit volume; ( \rho = \frac{m}{V} )
• Pressure: Force per unit area; ( P = \frac{F}{A} )
• Pascal's Principle: Pressure applied to a confined fluid is transmitted undiminished in all directions.

Thermodynamics

• Temperature: Measure of average kinetic energy of particles.
• Laws of Thermodynamics:
  1. Zeroth Law: If two bodies are in thermal equilibrium with a third body, they are in equilibrium with each other.
  2. First Law: Energy cannot be created or destroyed; ( \Delta U = Q - W )
  3. Second Law: Heat cannot spontaneously flow from a colder body to a hotter body.

Waves and Oscillations

• Wave: A disturbance that transfers energy from one point to another.
  • Types: Transverse and longitudinal.
• Frequency (f): Number of oscillations per unit time; ( f = \frac{1}{T} )
• Wave Speed: ( v = f \lambda ) (where ( \lambda ) is wavelength).

Electricity and Magnetism

• Ohm's Law: ( V = IR ) (Voltage equals current times resistance).
• Circuit Components: Resistors, capacitors, inductors.
• Magnetic Field: Region around a magnet where magnetic forces can be observed.

Optics

• Reflection: Bouncing back of light when it hits a surface.
• Refraction: Bending of light as it passes from one medium to another.
• Lenses: Convex (converging) and concave (diverging) lenses with different focal properties.

Modern Physics

• Quantum Mechanics: Study of particles at atomic and subatomic levels.
• Photoelectric Effect: Emission of electrons when light shines on a material.

Key Formulas

• Kinematic Equations
• Work, Energy, and Power equations
• Ohm's Law
• Wave speed equation

Study Tips

• Practice problem-solving with numerical examples.
• Understand concepts rather than rote memorization.
• Use diagrams and graphs to visualize concepts.

Basic Concepts

• Physics explores matter and energy interactions.
• Standard International (SI) units include meter (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol), and candela (cd).

Mechanics

• Kinematics: Analyzes motion ignoring forces.

  • Displacement indicates position change.
  • Velocity measures displacement change over time.
  • Acceleration gauges velocity change over time.
  • Key equations of motion:
    • ( v = u + at )
    • ( s = ut + \frac{1}{2}at^2 )
    • ( v^2 = u^2 + 2as )

• Dynamics: Focuses on forces affecting motion.

  • Newton's Laws:
    • First Law (Inertia): Objects remain in their state unless acted on.
    • Second Law: ( F = ma ), where force equals mass times acceleration.
    • Third Law: Every action has an equal and opposite reaction.

Work, Energy, and Power

• Work: Calculated as ( W = F \cdot d \cdot \cos(\theta) ).
• Energy: Ability to perform work.
  • Kinetic Energy: ( KE = \frac{1}{2}mv^2 ).
  • Potential Energy: ( PE = mgh ).
• Power: Rate at which work is done, defined as ( P = \frac{W}{t} ).

Properties of Matter

• Density: Mass-to-volume ratio expressed as ( \rho = \frac{m}{V} ).
• Pressure: Force per area calculated by ( P = \frac{F}{A} ).
• Pascal's Principle: Confined fluid pressure is transmitted uniformly in all directions.

Thermodynamics

• Temperature: Reflects average kinetic energy of particles.
• Laws of Thermodynamics:
  • Zeroth Law: Thermal equilibrium occurs among bodies in equilibrium with a third body.
  • First Law: Energy conservation expressed as ( \Delta U = Q - W ).
  • Second Law: Heat flow spontaneity is from hot to cold, not vice versa.

Waves and Oscillations

• Wave: Energy disturbance traveling from one location to another.
• Two main types: Transverse and longitudinal waves.
• Frequency (f): Oscillations per time unit, with ( f = \frac{1}{T} ).
• Wave Speed: Calculated as ( v = f \lambda ) (where ( \lambda ) represents wavelength).

Electricity and Magnetism

• Ohm's Law: Expressed as ( V = IR ), linking voltage, current, and resistance.
• Basic circuit components include resistors, capacitors, and inductors.
• Magnetic Field: Area surrounding a magnet where its influence can be felt.

Optics

• Reflection: Light bouncing off a surface when it strikes.
• Refraction: Light bending when transitioning between different media.
• Lenses:
  • Convex lenses converge light.
  • Concave lenses diverge light.

Modern Physics

• Quantum Mechanics: Investigates atomic and subatomic particle behavior.
• Photoelectric Effect: Phenomenon where light exposure causes electron emission from materials.

Key Formulas

• Kinematic equations for motion.
• Work, Energy, and Power calculations.
• Ohm's Law metrics.
• Wave speed formula.

Study Tips

• Engage with numerical problem-solving.
• Focus on conceptual understanding rather than memorization.
• Utilize diagrams and graphs for better visual comprehension.