#elastic vs inelastic collision

[medihertz]

Collision Insurance: A Complete Guide to Coverage, Costs, and Common Questions If you own a car, understanding collision insurance is crucial—it protects your vehicle from accident-related damage, but many drivers are unsure what it covers, when to drop it, and how it differs from comprehensive insurance. In this guide, we’ll answer the top-searched collision insurance questions,…

[enetarch-quantum-physics]

Topics to study for Quantum Physics

Calculus

Taylor Series

Sequences of Functions

Transcendental Equations

Differential Equations

Linear Algebra

Separation of Variables

Scalars

Vectors

Matrixes

Operators

Basis

Vector Operators

Inner Products

Identity Matrix

Unitary Matrix

Unitary Operators

Evolution Operator

Transformation

Rotational Matrix

Eigen Values

Coefficients

Linear Combinations

Matrix Elements

Delta Sequences

Vectors

Basics

Derivatives

Cartesian

Polar Coordinates

Cylindrical

Spherical

LaPlacian

Generalized Coordinate Systems

Waves

Components of Equations

Versions of the equation

Amplitudes

Time Dependent

Time Independent

Position Dependent

Complex Waves

Standing Waves

Nodes

AntiNodes

Traveling Waves

Plane Waves

Incident

Transmission

Reflection

Boundary Conditions

Probability

Probability

Probability Densities

Statistical Interpretation

Discrete Variables

Continuous Variables

Normalization

Probability Distribution

Conservation of Probability

Continuum Limit

Classical Mechanics

Position

Momentum

Center of Mass

Reduce Mass

Action Principle

Elastic and Inelastic Collisions

Physical State

Waves vs Particles

Probability Waves

Quantum Physics

Schroedinger Equation

Uncertainty Principle

Complex Conjugates

Continuity Equation

Quantization Rules

Heisenburg's Uncertianty Principle

Schroedinger Equation

TISE

Seperation from Time

Stationary States

Infinite Square Well

Harmonic Oscillator

Free Particle

Kronecker Delta Functions

Delta Function Potentials

Bound States

Finite Square Well

Scattering States

Incident Particles

Reflected Particles

Transmitted Particles

Motion

Quantum States

Group Velocity

Phase Velocity

Probabilities from Inner Products

Born Interpretation

Hilbert Space

Observables

Operators

Hermitian Operators

Determinate States

Degenerate States

Non-Degenerate States

n-Fold Degenerate States

Symetric States

State Function

State of the System

Eigen States

Eigen States of Position

Eigen States of Momentum

Eigen States of Zero Uncertainty

Eigen Energies

Eigen Energy Values

Eigen Energy States

Eigen Functions

Required properties

Eigen Energy States

Quantification

Negative Energy

Eigen Value Equations

Energy Gaps

Band Gaps

Atomic Spectra

Discrete Spectra

Continuous Spectra

Generalized Statistical Interpretation

Atomic Energy States

Sommerfels Model

The correspondence Principle

Wave Packet

Minimum Uncertainty

Energy Time Uncertainty

Bases of Hilbert Space

Fermi Dirac Notation

Changing Bases

Coordinate Systems

Cartesian

Cylindrical

Spherical - radii, azmithal, angle

Angular Equation

Radial Equation

Hydrogen Atom

Radial Wave Equation

Spectrum of Hydrogen

Angular Momentum

Total Angular Momentum

Orbital Angular Momentum

Angular Momentum Cones

Spin

Spin 1/2

Spin Orbital Interaction Energy

Electron in a Magnetic Field

ElectroMagnetic Interactions

Minimal Coupling

Orbital magnetic dipole moments

Two particle systems

Bosons

Fermions

Exchange Forces

Symmetry

Atoms

Helium

Periodic Table

Solids

Free Electron Gas

Band Structure

Transformations

Transformation in Space

Translation Operator

Translational Symmetry

Conservation Laws

Conservation of Probability

Parity

Parity In 1D

Parity In 2D

Parity In 3D

Even Parity

Odd Parity

Parity selection rules

Rotational Symmetry

Rotations about the z-axis

Rotations in 3D

Degeneracy

Selection rules for Scalars

Translations in time

Time Dependent Equations

Time Translation Invariance

Reflection Symmetry

Periodicity

Stern Gerlach experiment

Dynamic Variables

Kets, Bras and Operators

Multiplication

Measurements

Simultaneous measurements

Compatible Observable

Incompatible Observable

Transformation Matrix

Unitary Equivalent Observable

Position and Momentum Measurements

Wave Functions in Position and Momentum Space

Position space wave functions

momentum operator in position basis

Momentum Space wave functions

Wave Packets

Localized Wave Packets

Gaussian Wave Packets

Motion of Wave Packets

Potentials

Zero Potential

Potential Wells

Potentials in 1D

Potentials in 2D

Potentials in 3D

Linear Potential

Rectangular Potentials

Step Potentials

Central Potential

Bound States

UnBound States

Scattering States

Tunneling

Double Well

Square Barrier

Infinite Square Well Potential

Simple Harmonic Oscillator Potential

Binding Potentials

Non Binding Potentials

Forbidden domains

Forbidden regions

Quantum corral

Classically Allowed Regions

Classically Forbidden Regions

Regions

Landau Levels

Quantum Hall Effect

Molecular Binding

Quantum Numbers

Magnetic

Withal

Principle

Transformations

Gauge Transformations

Commutators

Commuting Operators

Non-Commuting Operators

Commutator Relations of Angular Momentum

Pauli Exclusion Principle

Orbitals

Multiplets

Excited States

Ground State

Spherical Bessel equations

Spherical Bessel Functions

Orthonormal

Orthogonal

Orthogonality

Polarized and UnPolarized Beams

Ladder Operators

Raising and Lowering Operators

Spherical harmonics

Isotropic Harmonic Oscillator

Coulomb Potential

Identical particles

Distinguishable particles

Expectation Values

Ehrenfests Theorem

Simple Harmonic Oscillator

Euler Lagrange Equations

Principle of Least Time

Principle of Least Action

Hamilton's Equation

Hamiltonian Equation

Classical Mechanics

Transition States

Selection Rules

Coherent State

Hydrogen Atom

Electron orbital velocity

principal quantum number

Spectroscopic Notation

=====

Common Equations

Energy (E) .. KE + V

Kinetic Energy (KE) .. KE = 1/2 m v^2

Potential Energy (V)

Momentum (p) is mass times velocity

Force equals mass times acceleration (f = m a)

Newtons' Law of Motion

Wave Length (λ) .. λ = h / p

Wave number (k) ..

k = 2 PI / λ

= p / h-bar

Frequency (f) .. f = 1 / period

Period (T) .. T = 1 / frequency

Density (λ) .. mass / volume

Reduced Mass (m) .. m = (m1 m2) / (m1 + m2)

Angular momentum (L)

Waves (w) ..

w = A sin (kx - wt + o)

w = A exp (i (kx - wt) ) + B exp (-i (kx - wt) )

Angular Frequency (w) ..

w = 2 PI f

= E / h-bar

Schroedinger's Equation

-p^2 [d/dx]^2 w (x, t) + V (x) w (x, t) = i h-bar [d/dt] w(x, t)

-p^2 [d/dx]^2 w (x) T (t) + V (x) w (x) T (t) = i h-bar [d/dt] w(x) T (t)

Time Dependent Schroedinger Equation

[ -p^2 [d/dx]^2 w (x) + V (x) w (x) ] / w (x) = i h-bar [d/dt] T (t) / T (t)

E w (x) = -p^2 [d/dx]^2 w (x) + V (x) w (x)

E i h-bar T (t) = [d/dt] T (t)

TISE - Time Independent

H w = E w

H w = -p^2 [d/dx]^2 w (x) + V (x) w (x)

H = -p^2 [d/dx]^2 + V (x)

-p^2 [d/dx]^2 w (x) + V (x) w (x) = E w (x)

Conversions

Energy / wave length ..

E = h f

E [n] = n h f

= (h-bar k[n])^2 / 2m

= (h-bar n PI)^2 / 2m

= sqr (p^2 c^2 + m^2 c^4)

Kinetic Energy (KE)

KE = 1/2 m v^2

= p^2 / 2m

Momentum (p)

p = h / λ

= sqr (2 m K)

= E / c

= h f / c

Angular momentum ..

p = n h / r, n = [1 .. oo] integers

Wave Length ..

λ = h / p

= h r / n (h / 2 PI)

= 2 PI r / n

= h / sqr (2 m K)

Constants

Planks constant (h)

Rydberg's constant (R)

Avogadro's number (Na)

Planks reduced constant (h-bar) .. h-bar = h / 2 PI

Speed of light (c)

electron mass (me)

proton mass (mp)

Boltzmann's constant (K)

Coulomb's constant

Bohr radius

Electron Volts to Jules

Meter Scale

Gravitational Constant is 6.7e-11 m^3 / kg s^2

History of Experiments

Light

Interference

Diffraction

Diffraction Gratings

Black body radiation

Planks formula

Compton Effect

Photo Electric Effect

Heisenberg's Microscope

Rutherford Planetary Model

Bohr Atom

de Broglie Waves

Double slit experiment

Light

Electrons

Casmir Effect

Pair Production

Superposition

Schroedinger's Cat

EPR Paradox

Examples

Tossing a ball into the air

Stability of the Atom

2 Beads on a wire

Plane Pendulum

Wave Like Behavior of Electrons

Constrained movement between two concentric impermeable spheres

Rigid Rod

Rigid Rotator

Spring Oscillator

Balls rolling down Hill

Balls Tossed in Air

Multiple Pullys and Weights

Particle in a Box

Particle in a Circle

Experiments

Particle in a Tube

Particle in a 2D Box

Particle in a 3D Box

Simple Harmonic Oscillator

Scattering Experiments

Diffraction Experiments

Stern Gerlach Experiment

Rayleigh Scattering

Ramsauer Effect

Davisson–Germer experiment

Theorems

Cauchy Schwarz inequality

Fourier Transformation

Inverse Fourier Transformation

Integration by Parts

Terminology

Levi Civita symbol

Laplace Runge Lenz vector

[sunenajain-blog]

Cracking IB Physics HL: Top Concepts You Must Master*  List and explain important concepts that repeatedly appear in Paper 1 & 2

IB Physics HL is known for its depth, rigor, and analytical challenge. To succeed, students must not only grasp complex theories but also apply them accurately in calculations and real-world contexts. With the right strategy and a focus on high-yield concepts, you can confidently approach Paper 1 (multiple choice) and Paper 2 (structured problems) and boost your IB score.

This guide lists the most frequently tested and foundational concepts in IB Physics HL—tailored for optimal exam preparation and performance.

⚛️ 1. Mechanics: The Core of Paper 1 and 2

Mechanics is the foundation of Physics HL and shows up in almost every exam.

Key Topics:

Kinematics: Equations of motion, velocity-time graphs, and projectile motion

Dynamics: Newton’s laws, friction, tension, and circular motion

Work, Energy, Power: Energy conservation, kinetic vs potential energy

Momentum: Impulse, conservation of linear momentum, collisions (elastic & inelastic)

📌 Exam Tip: Expect at least 4–6 marks on Paper 2 from projectile motion or Newton’s laws problems.

💡 2. Electricity and Magnetism

This unit is critical for both multiple-choice and calculation-heavy questions.

Key Topics:

Ohm’s Law and Resistivity

Kirchhoff’s Laws (complex circuits often appear on Paper 2)

Electromotive Force (emf) and internal resistance

Magnetic Fields and forces on moving charges/current-carrying wires

Electromagnetic Induction

📌 Common Mistake: Misapplying sign conventions in Lenz’s Law—review carefully!

🌊 3. Waves and Wave Phenomena

Mastering waves is essential, especially interference and diffraction.

Key Topics:

Wave Properties: Frequency, wavelength, amplitude, speed

Superposition and Standing Waves

Diffraction and Interference (Young’s double-slit experiment)

Doppler Effect (moving source vs moving observer)

📌 Formula to Know: v=fλv = f \lambdav=fλ; use in almost every wave question.

🌡️ 4. Thermal Physics and Kinetic Theory

Often underestimated, this topic yields consistent Paper 1 questions.

Key Topics:

Temperature and Heat Transfer

Specific Heat Capacity and Latent Heat

Kinetic Theory and Ideal Gas Law

PV diagrams and thermodynamic processes

📌 Paper 2 Alert: Internal energy change = work done + heat added — understand this balance.

☢️ 5. Atomic, Nuclear, and Quantum Physics

This HL-heavy topic frequently appears in both paper sections.

Key Topics:

Radioactive Decay Equations and half-life

Mass-Energy Equivalence (E = mc²)

Nuclear Fission and Fusion

Photoelectric Effect and quantum energy levels

De Broglie Wavelength

📌 Important: Understand how to apply Einstein’s photoelectric equation.

📡 6. Fields and Forces

Fields—gravitational, electric, and magnetic—are tested for conceptual understanding and calculations.

Key Topics:

Gravitational Fields and Potential Energy

Coulomb’s Law and Electric Field Strength

Electric Potential and Equipotential Surfaces

Uniform and Radial Fields

📌 Paper 1 Favorite: Comparing field lines and potential graphs.

🔌 7. Energy Production and Climate (Option Topic: Energy)

If you chose Option B: Energy Production, focus on:

Power plants and energy efficiency

Solar, wind, and nuclear power

Greenhouse effect and global warming

Energy density of fuels

📌 Graph Interpretation is frequently tested in this optional topic.

🧠 Strategy for Mastery

✅ Prioritize High-Weight Topics

Mechanics, Electricity, and Waves dominate the exam.

Focus on mastering these early and revisiting regularly.

✅ Practice Past Papers

IB Physics HL is highly pattern-based.

Review at least 5 years’ worth of Paper 1 and Paper 2 questions.

✅ Know Your Equations

Memorize the IB Physics formula booklet—but understand when and how to apply each equation.

✅ Sketch Diagrams

A well-drawn free-body diagram or field line sketch can help unlock 3–5 marks easily in Paper 2.

Final Thoughts

Cracking IB Physics HL isn’t just about raw intelligence—it’s about strategic focus, consistent practice, and mastering key concepts that appear again and again. If you internalize these high-yield areas and train with exam-style questions, you’ll walk into Paper 1 and Paper 2 prepared to perform with confidence.

Master the fundamentals. Understand the applications. And never stop practicing.

[janenguyenstudies]

Semester I Finals Recap

Writing

Task 1: Make a list of important points (note down) in the paragraph

Space exploration benefits

Then write a summary passage (150 words)

Task 2: Choose one:

1: Should English be a second language in Vietnam? Agree or Disagree? (list opposing arguments, then rebuttals, then your supporting evidence)

2: Copyright topic

Listening

Given 3 recordings:

1st: recording about Gifted children and their learning strategies

2nd: fill in the blanks, manuscript is the same as in https://www.theguardian.com/science/grrlscientist/2014/may/21/wild-mice-exercise-wheels-behaviour-stereotypy-neurosis

3rd: Fill in the blanks

https://www.ted.com/talks/julian_treasure_how_to_speak_so_that_people_want_to_listen

Chemistry

This test will not be too difficult. I suppose I would have scored higher if I had memorized the slides from the lecturer (Mr.Phong) instead of finding online resources to study. Some difficult questions include details in the slides that can be easily overlooked.

Examples: compare atmospheric pressure on rainy days vs sunny days, compare real gas vs ideal gas (P and T), calculate Gibbs free energy, enthalpy H, entropy S, elementary reactions (power the coefficient) , calculate Kc, decide the net ionic equation for given reaction, compare acid strength (HCN, HF, HClO), change Gibbs to Kc values, whether reaction is spontaneous (depends on G, S) . The written section had me scratching my head: decide the direction of equilibrium after changing volume, pressure, temperature...

Contents include Chapter 8-15 (in syllabus)

- > Gases and their properties, solutions, solids types, chemical reactions, rates of reactions, equilibrium, acid-base, thermodynamics.

I did a lot of exercises in section Acid-base equilibria, which include: calculate pH, Ka, Kc and in Solutions (calculate molarity, molality, vapor pressure,..) and even calculate the atom radius in crystalline structures. Turned out they were not tested as closely as Rate law, Equilibrium and Reaction order.

Calculus I

I only did half the exam correctly literally (sigh). Integrals are definitely not my strength. However, I have never scored higher than 60% on any math test ever. The integrals are strange to my untrained mind. I saved my miserable grades with assignments and watching basic integral technique videos (there is a whole youtube list). I suggest anyone not excelling in math not to be disheartened by the news. In fact, if you go over all the taught materials, write your notes neatly (a 2 sided A4 note is permitted), you will be able to answer 50% of the quiz, then ¾ of the written section (a cost optimization question, find the revenue function f(x), then differentiate f(x) to f’(x), let f’(x)=0 , find the highest value; a Simpson rule question; an area of a line and a parabola question).

My assignments

https://drive.google.com/file/d/17_VXU1D6VKuCT-JxfeYEJy9G8BIZ3ymb/view?usp=sharing https://drive.google.com/file/d/1BkFCo8FO4kJZyg0ZE3uSnsux4eAAjx_C/view?usp=sharing https://drive.google.com/file/d/10P6nCXdFsG2tv-Gnl5OO39bxYbrB2_IA/view?usp=sharing

My Video list  https://www.youtube.com/channel/UCNLRwiQSPlAn_hiEM2yWIwg

Biology

My Intro Bio teacher was very nice, so I went out of my way to prepare for this exam. I even spent a whole week prior to the exam to do my last research assignment (4-page-paper about causes and effects of increasing temperatures). As usual, I missed a lot of questions that could have been answered by learning the slides by heart. (I will not make the same mistake the next semester).

Examples: what is annelid (segmented worm), what is dorsal (opposite of upper), name all the parts of a flower (anther, stigma, filament, node, internode), lichen is mutualistic relationship, explain why antibody makes bacteria resistant is wrong, compare primary and secondary succession, does coelom form digestive tract?, poly-para- monophyletic branch, the largest unit of gene flow (species), define cryptic coloration, does humidity lead to increase in transcription, DNA cutting involve heating DNA strands.

Physics:

I had no trouble doing ⅗ of the test questions. They are actually similar to the sample problems in the textbook Fundamentals of Physics by Hallidays.

Q1: Use conservation of energy. E(mec2) = E(mec1) - E thermal (by friction)

Q2: Potential energy involving a spring force.

Q3: 2-direction inelastic collision (you have to calculate to decide whether it is elastic or not)

Q4: Rolling of a rigid body has kinetic energy of translation and rotation.

Q5: Quite hard though. But it was in the slides and I did not study it.

As for Physics, I advise against missing classes and falling behind, which guarantees failure in the final exam. My foolproof plan (guarantees at least ⅗ questions done) will be: Read textbook explanations of the topic before every class, then the night before lectures, read Mr.Hoi’s problems; after lectures, redo the sample problems, and if you have time, do the problems in the textbook. Before finals and midterms, make sure you have memorized the sample problems in textbook and slides. Then do the past exams posted by your TAs. Mr.Hoi’s extra problems can be done if you have extra time. ⅗ of the test covers the exact same problems every year (only applying the formulas, no extra thinking). So make sure you can identify which formulas to use.

[stepengineering-blog]

Basic Concepts Of Mechanical Engineering

It is pertinent to mention here that it is not easy for all engineers to remember all the basic concepts of mechanical engineering because over time, our memory fades and we can only remember those things that are used continuously in our daily life/work activities. As a mechanical engineering student, you should know the basic concepts of mechanical engineering that can be useful in interviews or anywhere. 

It is recommended that all mechanical engineers continue to review these concepts. It will help them improve work efficiency and performance in interviews to get better jobs. When you are a mechanical engineer, everyone expects you to respond accurately to some of the basic questions about mechanical engineering concepts. After a few years of graduation, mechanical engineers even forget what entropy and enthalpy are.

So please find the attachment for it below.

 Mechanical Engineering:

Mechanical Engineering - Introduction

Strength - Basic Definition

Resulting force

System of forces

Lami's theorem

Moment of a force

The beginning of the Varignon moments

Parallel forces

Couple - Moment of a couple

Gravity center

Moment of inertia

Friction and its types

Friction angle limiter

Angle of repose

Minimum force required to slide a body in a horizontal plane

Effort required to move the body in an inclined plane

Screw Jack

Lifting machine

Pulley systems

Truss or frame

Speed, Speed, Acceleration, Delay

Linear motion equations

The laws of Newton's movement

Mass, Weight, Momentum and Inertia

Beginning of D-Alembert

Movement of an elevator or elevator

Movement of two bodies connected by a rope on a pulley

Projectile movement

Equation of the trajectory of a projectile

Angular displacement

Angular velocity

Angular acceleration

Simple harmonic movement

Speed and acceleration of a particle in motion with a simple harmonic movement

Simple pendulum

Helical spring tightly wound

Composite pendulum

Percussion / oscillation center

Torsional pendulum

Centrifugal and centrifugal force.

Cant | Inclination angle

Elastic and inelastic collisions

Mechanical work | Definition | Formula

Mechanical power | Definition | Formula

Mechanical energy | Definition | The typesHydraulic machines:

Hydraulic machines - Introduction

Impact of water jets

Hydraulic turbines

Impulse turbines

Reaction turbines

Turbine draft tube

Specific speed of the turbine

Unit speed, unit discharge and unit power

Cavitation

Centrifugal pumps

Multistage centrifugal pumps

Specific speed of the centrifugal pump

Net positive suction head (NPSH)

Testing models and similarity of pumps

Reciprocating pump

Air ships

Various hydraulic machines

Thermodynamics:

Thermodynamics - Introduction

Thermodynamic system

Properties of a system

Thermal equilibrium

Laws of thermodynamics

Perfect gas laws

General gas equation

Characteristic equation of a gas

The law of joule

The avogadro law

Universal gas constant

Specific heat of a gas

Relationship Between Specific Heat

Thermodynamic processes of perfect gases

Constant volume process (isochoric)

Constant pressure process (isobaric)

Hyperbolic process

Constant temperature / isothermal process

Adiabatic process or isentropic process.

Polytropic process

Free expansion process

Strangulation process

General laws of expansion and compression.

Entropy

Thermodynamic cycle

Classification of thermodynamic cycles

Efficiency of a cycle

Carnot cycle

Stirling cycle

Ericsson cycle

Joule cycle

Otto cycle

Diesel cycleDouble combustion cycle

Gas turbines

Closed cycle gas turbine

Open cycle gas turbine

Thermal efficiency of the ideal gas turbine

Efficiency of the gas turbine

Fuels and combustion

Solid fuels

Liquid fuels

Gas fuels

Heating value of fuels

Fuel combustion

Theoretical or minimum air required for complete combustion

Mass of carbon in the combustion gases

Excess air mass supplied

IC engines:

IC Motors - Introduction

Two times vs four race engines

Sequence of operations in the IC engine

Gasoline engine valve timing diagram

Diesel engine valve timing diagram

Comparison of gasoline and diesel engines

Elimination of IC engines

Gasoline engine ignition system

Overfeeding of IC motors

Lubrication of IC engines

Government of IC engines

Carburetor of an IC motor

Spark plug on IC engines

Detonation or hit in IC engines

Octane Number - Classification of fuels of S.I.

Cetane number - Classification of CI engine fuels

IC motor tests

Thermodynamic tests for I.C. The engines

Effective average pressure indicated.

Indicated power of an IC motor

Motor brake power IC

Efficiency of an IC engine

[realtalk-tj]

can u guys list the topics taught in ap physics or send like a link to the syllabus (i couldnt find it online? i wanna know what topics are taught in the class.

Response from Flitwick: 

Sure! I’ll even do you one better - I’m breaking down topics by quarter, listing some details on some of the stuff covered within each unit, and to this post, I’ll attach someone else’s study guide that I found relatively useful for a read, at the very least. 

First Quarter: 

Calculus - not the entirety of BC, obviously, but just enough so you can differentiate and do a bit of integration. This is done in the context of the following bullet point... 

Kinematics - Describe the motion of objects! Understand that position, velocity, acceleration are vectors, and know how to describe common types of motion such as projectile motion, circular motion (uniform, non-uniform coming later), and simple harmonic. 

Forces - Understand Newton’s Laws, especially the Second Law, and use a systematic method to analyze the actions of the forces acting on an object (or multiple objects!). Know the most common types of forces - tension, friction, gravitational, normal, restorative (spring), drag, etc. 

If you make it here, you’ve gotten over the steepest part of the learning curve for AP Physics, in my opinion. But it doesn’t really get any easier...

Second Quarter: This part of the course is all about conserved quantities. (done in some order, because the physics dept. seems to be changing around the way they do these units...)

Linear Momentum - Understand what it is (and I like to think of it as what force delivers from object to object), under what conditions it is conserved, and use that to solve problems. Discuss the center of mass and the center of mass frame. Usually, a discussion about rockets and collisions (elastic vs. inelastic).

Energy - Learn about conservative forces, potential energy, and generally, the conservation of mechanical energy. Understand the Work-Energy Theorem and what work is. Use the conservation of energy to simplify your analysis of easy problems(!!) and solve difficult problems. 

Rotation and Angular Momentum - Understand how to describe the rotation of an object (up to constant angular acceleration). Describe rotational equivalents of stuff in all the previous units, including torque, angular momentum, and rotational kinetic energy. Understand what the moment of inertia of a rigid body is and how to calculate it. 

Gravitation - Kind of a side topic, but also kind of invokes all the previous units, and is a good lead-up into E&M. Study Kepler’s Laws and Newton’s Law of Universal Gravitation, understand what they mean, and calculate stuff from them. Calculate gravitational fields using Universal Gravitation and superposition (integrating). 

Third Quarter: Electromagnetism makes an entrance...

Electrostatics - Learn about electric charge, and how they are sources/sinks of electric fields. Calculate electric fields using superposition and Coulomb’s inverse square law, and take shortcuts using symmetry and Gauss’ Law. Incorporate this knowledge with mechanical applications. Describe what electric potential is, and understand what are equipotentials and why they are special. 

Conductors/Circuits - Understand what a conductor is, and what properties they have in a steady state. Learn about the property of capacitance, and understand how to calculate it for a parallel plate capacitor (and other special setups). Understand Ohm’s Law (including in the differential form) and how you can use it to describe resistance, current, voltage. Combine this with Kirchoff’s Loop Rules (essentially glorified conservation of energy/charge) to analyze basic circuits. 

Fourth Quarter: 

Conductors/Circuits - Learn about time-dependent circuit problems, most notably RC circuits, and then later RL and LC circuits. Understand how capacitors store energy. Use Kirchoff’s Rules more and analyze more complex circuits, and answer more difficult questions with a more qualitative/intuitive understanding of what goes on in a circuit. 

Magnetism - Learn about the Lorentz Force Law, and how magnetic fields apply a force on a charge, but DON’T actually do work to the charge. Understand that magnetic fields always form closed loops and that we can calculate their strength using the Biot-Savart Law or take a shortcut with Ampere’s Law. Know how to apply Faraday-Lenz to bring back (magnetic) flux. Look at the solenoid as a case study as an inductor, and understand the property of inductance. 

There’s usually some extra stuff that the AP teachers like to do, like correcting Ampere’s Law to assemble all four of Maxwell’s equations for you to finish off the year, and then have some AP review. I’ve heard in past years they even do some special relativity if they have time, but often they do some sort of project to end the year. 

As promised, a link to someone else’s study guide for AP Physics that I kind of like/is useful, even if it’s got some errors and looks kinda scuffed: https://www.facebook.com/groups/316519978541744/permalink/924092767784459/

Good luck in AP Physics next year! It’s a tough class, and I hope you can get through it :)

[fernando-j-scherf-blog]

Planet Lander - EXPLOSIONS

During the last few days I’ve been implementing more complex collisions, cooler explosions, and the ability to shoot highly destructive lasers.

For the collisions, I wanted different behaviors for different cases:

Planet vs Anything:

If something collides against the planet, it is destroyed an in its place an explosion is created.

In the final game, if the collision is against an asteroid, the player will lose some points, because his job was to defend the planet and he let millions of its inhabitants die. If the collision is against the ship, the player will lose a life.

Asteroids vs Asteroids:

For this type, I programmed elastic collisions. This means, that the total kinetic energy (The sum of the energies that the objects have due to their motion) and the total momentum (The sum of the products of the mass and velocity of each object) that the two Spacial Rocks have before the collision, must be the same after the collision. This means, that the asteroids will bounce off each other as if they were balls on a pool table.

Asteroids vs Space Dust:

The “Space Dust” are the little particles that you see flying around the screen. They serve an aesthetic purpose, and nothing more. These particles are created when:

Each game starts. They are supposed to represent very little, insignificant rocks that are just going around the planet.

The player gives impulse to the ship to move it forward or rotate it.

An explosion is created.

And when they get in contact with an asteroid, they are simply eliminated. My idea is that they just become part of the asteroid.

Asteroid vs Ship:

The ship is destroyed, an explosion is created, and the player loses a life. This is more of a perfectly inelastic collision, where the colliding objects are bound together, instead of bouncing off each other, and kinetic energy is lost. Imagine that the pieces of the ships get stuck into the asteroid. The same could be said about the Space Dust: They get into the asteroid, and after the collision they both keep moving with the same speed and direction. Perfectly Inelastic Collision.

Asteroid vs Laser:

Again, I use elastic collisions. When the laser hits a rock, the program first calculates the new velocities for the asteroid and the laser, as if they were to bounce off each other (Again: Like balls on a pool table). But instead, the laser is eliminated and the rock is destroyed, and an explosion and two smaller rocks (These two smaller rocks each have half of the total surface of the original, bigger rock) are created, and the new velocity that was calculated for the big asteroid is given to them, so after the impact, the big asteroid not only becomes two smaller asteroids, but also they change directions realistically. And, yes, I know that technically this should not be an elastic collision, because after an explosion energy is lost from the system, but for what I want, this is working perfectly.

This is all for now! I hope you find some of this interesting. I hope I didn’t commit any mistake while writing. English is not my original language!