Online courses directory (381)

Magnet near Compass. Tracing a Magnetic Field. Tracing a magnetic field. Discovery of Magnetic Fields. Magnet and iron filings. Magnetic field. 3D magnet with field. Magnetic Permeability. Increase Strength of Magnet. What's Next?.

Are 2 magnets stronger than 1?. Measure the Earth!. Earth's Magnetic Field (how to measure). Force over Distance. Inverse Cube Law (deflection method). Inverse Square Relationship. Inverse Cube Law (Method of Oscillation).

Zinc Copper cell (reduction-oxidation). How to Measure?. Battery Meter (Galvanometer). How Many Turns?. Electrolyte Test (pure water vs. vinegar). Reverse Electrodes (polarity). Electrolyte (strong acid test). Electrolyte (salt test). Electrode (distance test). Electrolyte (temperature test). Electrode (surface area test). Standard Cell. How much electrolyte does a single cell need?. What's Next?.

Discovery of Electromagnetism. Experiment: Electromangetism. Electromagnetic Field (above vs. below). Electromagnetic Field (forward vs. reverse). Electromagnetic Field (loop). Right-Hand Rule. Battery Meter (Galvanometer).

Series Load. Pencil Resistor. Variable Resistor (Pencil). Listen to Variable Resistance. What's Next?.

Electromagnet (construction tip). Electromagnet (penny powered). Understanding Force.

Spinning Compass. Build your own motor. What's Next.

Discovery of Triboelectric effect. Pith Ball Electroscope. Foil Leaf Electroscope. What's Next?.

Sal works through California Standards Test problems. Whether you are in California and studying for that test or just want additional practice, this is a good place to review the major math concepts. CA Algebra I: Number Properties and Absolute Value. CA Algebra I: Simplifying Expressions. CA Algebra I: Simple Logical Arguments. CA Algebra I: Graphing Inequalities. CA Algebra I: Slope and Y-intercept. CA Algebra I: Systems of Inequalities. CA Algebra I: Simplifying Expressions. CA Algebra I: Factoring Quadratics. CA Algebra I: Completing the Square. CA Algebra I: Quadratic Equation. CA Algebra I: Quadratic Roots. CA Algebra I: Rational Expressions 1. CA Algebra I: Rational Expressions 2. CA Algebra I: Word Problems. CA Algebra I: More Word Problems. CA Algebra I: Functions. California Standards Test: Algebra II. California Standards Test: Algebra II (Graphing Inequalities). CA Standards: Algebra II (Algebraic Division/Multiplication). CA Standards: Algebra II. Algebra II: Simplifying Polynomials. Algebra II: Imaginary and Complex Numbers. Algebra II: Complex numbers and conjugates. Algebra II: Quadratics and Shifts. Examples: Graphing and interpreting quadratics. Hyperbola and parabola examples. Algebra II: Circles and Logarithms. Algebra II: Logarithms Exponential Growth. Algebra II: Logarithms and more. Algebra II: Functions, Combinatorics. Algebra II: binomial Expansion and Combinatorics. Algebra II: Binomial Expansions, Geometric Series Sum. Algebra II: Functions and Probability. Algebra II: Probability and Statistics. Algebra II: Mean and Standard Deviation. CA Geometry: deductive reasoning. CA Geometry: Proof by Contradiction. CA Geometry: More Proofs. CA Geometry: Similar Triangles 1. CA Geometry: Similar Triangles 2. CA Geometry: More on congruent and similar triangles. CA Geometry: Triangles and Parallelograms. CA Geometry: Area, Pythagorean Theorem. CA Geometry: Area, Circumference, Volume. CA Geometry: Pythagorean Theorem, Area. CA Geometry: Exterior Angles. CA Geometry: Deducing Angle Measures. CA Geometry: Pythagorean Theorem, Compass Constructions. CA Geometry: Compass Construction. CA Geometry: Basic Trigonometry. CA Geometry: More Trig. CA Geometry: Circle Area Chords Tangent. CA Geometry: Secants and Translations. CA Algebra I: Number Properties and Absolute Value. CA Algebra I: Simplifying Expressions. CA Algebra I: Simple Logical Arguments. CA Algebra I: Graphing Inequalities. CA Algebra I: Slope and Y-intercept. CA Algebra I: Systems of Inequalities. CA Algebra I: Simplifying Expressions. CA Algebra I: Factoring Quadratics. CA Algebra I: Completing the Square. CA Algebra I: Quadratic Equation. CA Algebra I: Quadratic Roots. CA Algebra I: Rational Expressions 1. CA Algebra I: Rational Expressions 2. CA Algebra I: Word Problems. CA Algebra I: More Word Problems. CA Algebra I: Functions. California Standards Test: Algebra II. California Standards Test: Algebra II (Graphing Inequalities). CA Standards: Algebra II (Algebraic Division/Multiplication). CA Standards: Algebra II. Algebra II: Simplifying Polynomials. Algebra II: Imaginary and Complex Numbers. Algebra II: Complex numbers and conjugates. Algebra II: Quadratics and Shifts. Examples: Graphing and interpreting quadratics. Hyperbola and parabola examples. Algebra II: Circles and Logarithms. Algebra II: Logarithms Exponential Growth. Algebra II: Logarithms and more. Algebra II: Functions, Combinatorics. Algebra II: binomial Expansion and Combinatorics. Algebra II: Binomial Expansions, Geometric Series Sum. Algebra II: Functions and Probability. Algebra II: Probability and Statistics. Algebra II: Mean and Standard Deviation. CA Geometry: deductive reasoning. CA Geometry: Proof by Contradiction. CA Geometry: More Proofs. CA Geometry: Similar Triangles 1. CA Geometry: Similar Triangles 2. CA Geometry: More on congruent and similar triangles. CA Geometry: Triangles and Parallelograms. CA Geometry: Area, Pythagorean Theorem. CA Geometry: Area, Circumference, Volume. CA Geometry: Pythagorean Theorem, Area. CA Geometry: Exterior Angles. CA Geometry: Deducing Angle Measures. CA Geometry: Pythagorean Theorem, Compass Constructions. CA Geometry: Compass Construction. CA Geometry: Basic Trigonometry. CA Geometry: More Trig. CA Geometry: Circle Area Chords Tangent. CA Geometry: Secants and Translations.

Questions from previous IIT JEEs. IIT JEE Trigonometry Problem 1. IIT JEE Perpendicular Planes (Part 1). IIT JEE Perpendicular Plane (part 2). IIT JEE Complex Root Probability (part 1). IIT JEE Complex Root Probability (part 2). IIT JEE Position Vectors. IIT JEE Integral Limit. IIT JEE Algebraic Manipulation. IIT JEE Function Maxima. IIT JEE Diameter Slope. IIT JEE Hairy Trig and Algebra (part 1). IIT JEE Hairy Trig and Algebra (Part 2). IIT JEE Hairy Trig and Algebra (Part 3). IIT JEE Complex Numbers (part 1). IIT JEE Complex Numbers (part 2). IIT JEE Complex Numbers (part 3). IIT JEE Differentiability and Boundedness. IIT JEE Integral with Binomial Expansion. IIT JEE Symmetric and Skew-Symmetric Matrices. IIT JEE Trace and Determinant. IIT JEE Divisible Determinants. IIT JEE Circle Hyperbola Intersection. IIT JEE Circle Hyperbola Common Tangent Part 1. IIT JEE Circle Hyperbola Common Tangent Part 2. IIT JEE Circle Hyperbola Common Tangent Part 3. IIT JEE Circle Hyperbola Common Tangent Part 4. IIT JEE Circle Hyperbola Common Tangent Part 5. IIT JEE Trigonometric Constraints. IIT JEE Trigonometric Maximum. Vector Triple Product Expansion (very optional). IIT JEE Lagrange's Formula. Tangent Line Hyperbola Relationship (very optional). 2010 IIT JEE Paper 1 Problem 50 Hyperbola Eccentricity. Normal vector from plane equation. Point distance to plane. Distance Between Planes. Complex Determinant Example. Series Sum Example. Trigonometric System Example. Simple Differential Equation Example. IIT JEE Trigonometry Problem 1. IIT JEE Perpendicular Planes (Part 1). IIT JEE Perpendicular Plane (part 2). IIT JEE Complex Root Probability (part 1). IIT JEE Complex Root Probability (part 2). IIT JEE Position Vectors. IIT JEE Integral Limit. IIT JEE Algebraic Manipulation. IIT JEE Function Maxima. IIT JEE Diameter Slope. IIT JEE Hairy Trig and Algebra (part 1). IIT JEE Hairy Trig and Algebra (Part 2). IIT JEE Hairy Trig and Algebra (Part 3). IIT JEE Complex Numbers (part 1). IIT JEE Complex Numbers (part 2). IIT JEE Complex Numbers (part 3). IIT JEE Differentiability and Boundedness. IIT JEE Integral with Binomial Expansion. IIT JEE Symmetric and Skew-Symmetric Matrices. IIT JEE Trace and Determinant. IIT JEE Divisible Determinants. IIT JEE Circle Hyperbola Intersection. IIT JEE Circle Hyperbola Common Tangent Part 1. IIT JEE Circle Hyperbola Common Tangent Part 2. IIT JEE Circle Hyperbola Common Tangent Part 3. IIT JEE Circle Hyperbola Common Tangent Part 4. IIT JEE Circle Hyperbola Common Tangent Part 5. IIT JEE Trigonometric Constraints. IIT JEE Trigonometric Maximum. Vector Triple Product Expansion (very optional). IIT JEE Lagrange's Formula. Tangent Line Hyperbola Relationship (very optional). 2010 IIT JEE Paper 1 Problem 50 Hyperbola Eccentricity. Normal vector from plane equation. Point distance to plane. Distance Between Planes. Complex Determinant Example. Series Sum Example. Trigonometric System Example. Simple Differential Equation Example.

Start your own robotics project with Spout, Spider, and Bit-zee!. 3rd graders build robots at Santa Rita Elementary School. Parts list for Spout. Tool list for Spout. Spout step by step PDF. See inside Spout's motors and switches. Spout 1. Spout 2. Spout 3. Spout 4. Spout 5. Spout 6. Spout 7. Spout 8. Spout 9. Spout 10. Spout 11. Spout OOP: with Maze. The goal of Spout. 1 Spout Introduction (with solder). 2 Attach Spout's lever switches and motors. 3 Attach Spout's wires and connectors. 4 Attach Spout's sliding switches and resistors. 5 Connect Spout's antenna. 6 Attach Spout's LED eyes. 6th graders learn to build a Spider robot. Fun with a Spider Bot. Parts list for Spider. Tools list for Spider. 1 Spider parts and tools. 2 Hacking Spider's click n' stick. 3 Creating the battery and motor mounts for Spider. 4 Attach Spider's click n' stick base to the batteries and thread his wires. 5 Attach Spider's motor controller and wire his motors. 6 Connect Spider's power switch and run the power wires to the motor controller. 7 Attach and adjust the Spider's bezel. 8 Attach Spider's wheels. 9 Make the connnectors for Spider's Arduino Nano. 10 Spider Connect the power and signal wires from the motor controller to the Arduino. 11 Attach Spider's LED eyes. 12 Connect Spider's stablizer bar. 13 Spider's Romance. 14 Teaching Spider to dance. 15 Ben Eater's Spider Bot. Parts for Bit-zee and It-zee. Tools for Bit-zee and It-zee. 1. Bit-zee. 2. Bit-zee (long version). 3. Bit-zee Bot Introduction. 4. Bit-zee planning and propulsion. 5. Bit-zee's bits. 6. Bit-zee's chassis/frame. 7. Bit-zee's wheel mounts and fenders. 8. Bit-zee's component mounting holes. 9. Bit-zee's batteries. 10. Improving the battery wires. 11. Connecting Bit-zee's power wires and on-off switch. 12. Bit-zee's motors. 13. Why does Bit-zee need a motor controller?. 14. Bit-zee's motor controller. 15. Attaching and wiring Bit-zee's motor controller. 16. Attaching Bit-zee's Arduino. 17. How to hotwire a digital camera. 18. Attaching Bit-zee's digital camera. 19. Bit zee's 5 Volt power distribution board. 20. Hacking and attaching a digital recorder/player to Bit-zee. 21. Making a power connector for the Arduino. 22. Attaching Bit-zee's prototype board. 23. Connecting the motor controller to the Arduino. 24. Connecting Bit-zee's camera to the Arduino. 25. Bit-zee's bumper switches. 26. Bit-zee's eyes. 27. Bit-zee's IR sensor. 28. Bit-zee's shell. 29. Camera wiring update. 30. Load the Code for It-zee and Bit-zee. 3rd graders build robots at Santa Rita Elementary School. Parts list for Spout. Tool list for Spout. Spout step by step PDF. See inside Spout's motors and switches. Spout 1. Spout 2. Spout 3. Spout 4. Spout 5. Spout 6. Spout 7. Spout 8. Spout 9. Spout 10. Spout 11. Spout OOP: with Maze. The goal of Spout. 1 Spout Introduction (with solder). 2 Attach Spout's lever switches and motors. 3 Attach Spout's wires and connectors. 4 Attach Spout's sliding switches and resistors. 5 Connect Spout's antenna. 6 Attach Spout's LED eyes. 6th graders learn to build a Spider robot. Fun with a Spider Bot. Parts list for Spider. Tools list for Spider. 1 Spider parts and tools. 2 Hacking Spider's click n' stick. 3 Creating the battery and motor mounts for Spider. 4 Attach Spider's click n' stick base to the batteries and thread his wires. 5 Attach Spider's motor controller and wire his motors. 6 Connect Spider's power switch and run the power wires to the motor controller. 7 Attach and adjust the Spider's bezel. 8 Attach Spider's wheels. 9 Make the connnectors for Spider's Arduino Nano. 10 Spider Connect the power and signal wires from the motor controller to the Arduino. 11 Attach Spider's LED eyes. 12 Connect Spider's stablizer bar. 13 Spider's Romance. 14 Teaching Spider to dance. 15 Ben Eater's Spider Bot. Parts for Bit-zee and It-zee. Tools for Bit-zee and It-zee. 1. Bit-zee. 2. Bit-zee (long version). 3. Bit-zee Bot Introduction. 4. Bit-zee planning and propulsion. 5. Bit-zee's bits. 6. Bit-zee's chassis/frame. 7. Bit-zee's wheel mounts and fenders. 8. Bit-zee's component mounting holes. 9. Bit-zee's batteries. 10. Improving the battery wires. 11. Connecting Bit-zee's power wires and on-off switch. 12. Bit-zee's motors. 13. Why does Bit-zee need a motor controller?. 14. Bit-zee's motor controller. 15. Attaching and wiring Bit-zee's motor controller. 16. Attaching Bit-zee's Arduino. 17. How to hotwire a digital camera. 18. Attaching Bit-zee's digital camera. 19. Bit zee's 5 Volt power distribution board. 20. Hacking and attaching a digital recorder/player to Bit-zee. 21. Making a power connector for the Arduino. 22. Attaching Bit-zee's prototype board. 23. Connecting the motor controller to the Arduino. 24. Connecting Bit-zee's camera to the Arduino. 25. Bit-zee's bumper switches. 26. Bit-zee's eyes. 27. Bit-zee's IR sensor. 28. Bit-zee's shell. 29. Camera wiring update. 30. Load the Code for It-zee and Bit-zee.

Videos exploring the way things work. What is inside an alarm clock radio?. What is inside a coffee maker?. What is inside a tap light?. What is inside a hair dryer? (1 of 2). What is inside a hair dryer? (2 of 2). Compare the hair dryer motor to the one you can build. What is inside a DVD player? (1 of 5). What is inside a DVD player? (2 of 5). What is inside a DVD player? (3 of 5). What is inside a DVD player? (4 of 5). What is inside a DVD player? (5 of 5). What is inside a universal remote control?. What is inside a digital camera? (1 of 2). What is inside a digital camera? (2 of 2). What is inside an alarm clock radio?. What is inside a coffee maker?. What is inside a tap light?. What is inside a hair dryer? (1 of 2). What is inside a hair dryer? (2 of 2). Compare the hair dryer motor to the one you can build. What is inside a DVD player? (1 of 5). What is inside a DVD player? (2 of 5). What is inside a DVD player? (3 of 5). What is inside a DVD player? (4 of 5). What is inside a DVD player? (5 of 5). What is inside a universal remote control?. What is inside a digital camera? (1 of 2). What is inside a digital camera? (2 of 2).

Rediscover the most important observations in history. Discovery of Magnetism. Compass: which way is north?. Floating Magnet. Compass Build (stroke direction). Compass Build (magnet orientation). Neutralize a Compass. Compass Interactions. Magnetising materials. What's Next?. Magnet near Compass. Tracing a Magnetic Field. Tracing a magnetic field. Discovery of Magnetic Fields. Magnet and iron filings. Magnetic field. 3D magnet with field. Magnetic Permeability. Increase Strength of Magnet. What's Next?. Are 2 magnets stronger than 1?. Measure the Earth!. Earth's Magnetic Field (how to measure). Force over Distance. Inverse Cube Law (deflection method). Inverse Square Relationship. Inverse Cube Law (Method of Oscillation). Zinc Copper cell (reduction-oxidation). How to Measure?. Battery Meter (Galvanometer). How Many Turns?. Electrolyte Test (pure water vs. vinegar). Reverse Electrodes (polarity). Electrolyte (strong acid test). Electrolyte (salt test). Electrode (distance test). Electrolyte (temperature test). Electrode (surface area test). Standard Cell. How much electrolyte does a single cell need?. What's Next?. Discovery of Electromagnetism. Experiment: Electromangetism. Electromagnetic Field (above vs. below). Electromagnetic Field (forward vs. reverse). Electromagnetic Field (loop). Right-Hand Rule. Battery Meter (Galvanometer). Series Load. Pencil Resistor. Variable Resistor (Pencil). Listen to Variable Resistance. What's Next?. Electromagnet (construction tip). Electromagnet (penny powered). Understanding Force. Spinning Compass. Build your own motor. What's Next. Discovery of Triboelectric effect. Pith Ball Electroscope. Foil Leaf Electroscope. What's Next?. Discovery of Magnetism. Compass: which way is north?. Floating Magnet. Compass Build (stroke direction). Compass Build (magnet orientation). Neutralize a Compass. Compass Interactions. Magnetising materials. What's Next?. Magnet near Compass. Tracing a Magnetic Field. Tracing a magnetic field. Discovery of Magnetic Fields. Magnet and iron filings. Magnetic field. 3D magnet with field. Magnetic Permeability. Increase Strength of Magnet. What's Next?. Are 2 magnets stronger than 1?. Measure the Earth!. Earth's Magnetic Field (how to measure). Force over Distance. Inverse Cube Law (deflection method). Inverse Square Relationship. Inverse Cube Law (Method of Oscillation). Zinc Copper cell (reduction-oxidation). How to Measure?. Battery Meter (Galvanometer). How Many Turns?. Electrolyte Test (pure water vs. vinegar). Reverse Electrodes (polarity). Electrolyte (strong acid test). Electrolyte (salt test). Electrode (distance test). Electrolyte (temperature test). Electrode (surface area test). Standard Cell. How much electrolyte does a single cell need?. What's Next?. Discovery of Electromagnetism. Experiment: Electromangetism. Electromagnetic Field (above vs. below). Electromagnetic Field (forward vs. reverse). Electromagnetic Field (loop). Right-Hand Rule. Battery Meter (Galvanometer). Series Load. Pencil Resistor. Variable Resistor (Pencil). Listen to Variable Resistance. What's Next?. Electromagnet (construction tip). Electromagnet (penny powered). Understanding Force. Spinning Compass. Build your own motor. What's Next. Discovery of Triboelectric effect. Pith Ball Electroscope. Foil Leaf Electroscope. What's Next?.

Ping pong ball launcher introduction. Build a ping pong ball launcher . Update and modify your ping pong ball launcher. Ping pong ball launcher introduction. Build a ping pong ball launcher . Update and modify your ping pong ball launcher.

Thermo Can. Thermo Can.

Discovery Lab Overview. Monty Hall. Icosahedron. Lemonade Stand. Magician's Guess. Bridge Building. Explore Instructor Reflections. Lego Sumo Robots. Rube Goldberg. Spout Bot Innovation. Spout Bot Build. Spout Comes Alive. Spout Instructor Reflections. Build Up to Bridge Testing. Exhibition Day. Discovery Lab Overview. Monty Hall. Icosahedron. Lemonade Stand. Magician's Guess. Bridge Building. Explore Instructor Reflections. Lego Sumo Robots. Rube Goldberg. Spout Bot Innovation. Spout Bot Build. Spout Comes Alive. Spout Instructor Reflections. Build Up to Bridge Testing. Exhibition Day.

Khan Academy's Discovery Lab Offers Hands-On Learning. Khan DL Week 3 - Vannesa, Melvin & Greta. Khan DL Week 2 - Philip and Miles. Khan DL Week 2 - Arshia. AntBots in action. Khan Academy's Discovery Lab Offers Hands-On Learning. Khan DL Week 3 - Vannesa, Melvin & Greta. Khan DL Week 2 - Philip and Miles. Khan DL Week 2 - Arshia. AntBots in action.

The core ideas in microeconomics. Supply, demand and equilibrium. Introduction to Economics. Law of Demand. Change in Expected Future Prices and Demand. Price of Related Products and Demand. Changes in Income, Population, or Preferences. Normal and Inferior Goods. Inferior Goods Clarification. Law of Supply. Factors Affecting Supply. Long Term Supply Curve. Market Equilibrium. Changes in Market Equilibrium. Breakdown of Gas Prices. Short-Run Oil Prices. Introduction to Economics. Law of Demand. Change in Expected Future Prices and Demand. Price of Related Products and Demand. Changes in Income, Population, or Preferences. Normal and Inferior Goods. Inferior Goods Clarification. Law of Supply. Factors Affecting Supply. Long Term Supply Curve. Market Equilibrium. Changes in Market Equilibrium. Breakdown of Gas Prices. Short-Run Oil Prices.

Price elasticity of demand and supply. How sensitive are things to change in price. Price Elasticity of Demand. More on Elasticity of Demand. Perfect Inelasticity and Perfect Elasticity of Demand. Constant Unit Elasticity. Total Revenue and Elasticity. More on Total Revenue and Elasticity. Cross Elasticity of Demand. Elasticity of Supply. Elasticity and Strange Percent Changes. Price Elasticity of Demand. More on Elasticity of Demand. Perfect Inelasticity and Perfect Elasticity of Demand. Constant Unit Elasticity. Total Revenue and Elasticity. More on Total Revenue and Elasticity. Cross Elasticity of Demand. Elasticity of Supply. Elasticity and Strange Percent Changes.

Demand Curve as Marginal Benefit Curve. Consumer Surplus Introduction. Total Consumer Surplus as Area. Producer Surplus. Rent Control and Deadweight Loss. Minimum Wage and Price Floors. Taxation and Dead Weight Loss. Percentage Tax on Hamburgers. Taxes and Perfectly Inelastic Demand. Taxes and Perfectly Elastic Demand. Negative Externalities. Taxes for Factoring in Negative Externalities. Positive Externalities. Tragedy of the Commons. Demand Curve as Marginal Benefit Curve. Consumer Surplus Introduction. Total Consumer Surplus as Area. Producer Surplus. Rent Control and Deadweight Loss. Minimum Wage and Price Floors. Taxation and Dead Weight Loss. Percentage Tax on Hamburgers. Taxes and Perfectly Inelastic Demand. Taxes and Perfectly Elastic Demand. Negative Externalities. Taxes for Factoring in Negative Externalities. Positive Externalities. Tragedy of the Commons.