Khan Academy on a Stick
Forces and Newton's laws of motion
This tutorial is the meat of much of classical physics. We think about what a force is and how Newton changed the world's (and possibly your) view of how reality works.
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Newton's first law of motion
Basic primer on Newton's First Law of Motion
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Newton's first law of motion concepts
A little quiz on some of the ideas in Newton's first law
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More on Newton's first law of motion
Newton's First Law (Galileo's Law of Inertia).
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Newton's second law of motion
Newton's Second Law of Motion: F=ma
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Newton's third law of motion
Every action has an equal and opposite reaction
Newton's laws of motion
This tutorial will expose you to the foundation of classical mechanics--Newton's laws. On one level they are intuitive, on another lever they are completely counter-intuitive. Challenge your take on reality and watch this tutorial. The world will look very different after you're done.
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Normal force and contact force
The force that keeps a block of ice from falling towards the center of the earth
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Normal force in an elevator
How the normal force changes when an elevator accelerates
Normal force and contact force
A dog is balancing on one arm on my head. Is my head applying a force to the dog's hand? If it weren't, wouldn't there be nothing to offset the pull of gravity causing the acrobatic dog to fall? What would we call this force? Can we have a general term from the component of a contact force that acts perpendicular to the plane of contact? These are absolutely normal questions to ask.
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Balanced and unbalanced forces
Primer on identifying balanced and unbalanced forces
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Unbalanced forces and motion
Thinking about what is true about how unbalanced forces relate to motion and acceleration
Balanced and unbalanced forces
You will often hear physics professors be careful to say "net force" or "unbalanced force" rather than just "force". Why? This tutorial explains why and might give you more intuition about Newton's laws in the process.
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Slow sock on Lubricon VI
What would happen to a slowly moving frozen sock on a frictionless planet
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Normal forces on Lubricon VI
Whether the normal force balances the force of gravity for a frozen sock or banana
Slow sock on Lubricon VI
This short tutorial will have you dealing with orbiting frozen socks in order to understand whether you understand Newton's Laws. We also quiz you a bit during the videos just to make sure that you aren't daydreaming about what you would do with a frozen sock.
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Inclined plane force components
Figuring out the components of the force due to gravity that are parallel and perpendicular to the surface of an inclined plane
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Ice accelerating down an incline
Figuring out the acceleration of ice down a plane made of ice
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Force of friction keeping the block stationary
Block of wood kept stationary by the force of friction (Correction made in next video)
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Correction to force of friction keeping the block stationary
Correction to Force of Friction Keeping the Block Stationary
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Force of friction keeping velocity constant
Calculating the coefficient of kinetic friction (correction made in next video)
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Intuition on static and kinetic friction comparisons
Why static friction is harder to overcome than kinetic friction
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Static and kinetic friction example
Thinking about the coefficients of static and kinetic friction
Inclined planes and friction
We've all slid down slides/snow-or-mud-covered-hills/railings at some point in our life (if not, you haven't really lived) and noticed that the smoother the surface the more we would accelerate (try to slide down a non-snow-or-mud-covered hill). This tutorial looks into this in some depth. We'll look at masses on inclined planes and think about static and kinetic friction.
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Introduction to tension
An introduction to tension. Solving for the tension(s) in a set of wires when a weight is hanging from them.
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Introduction to tension (part 2)
A slightly more difficult tension problem.
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Tension in an accelerating system and pie in the face
The second part to the complicated problem. We figure out the tension in the wire connecting the two masses. Then we figure our how much we need to accelerate a pie for it to safely reach a man's face.
Tension
Bad commute? Baby crying? Bills to pay? Looking to take a bath with some Calgon (do a search on YouTube for context) to ease your tension? This tutorial has nothing (actually little, not nothing) to do with that. So far, most of the forces we've been dealing with are forces of "pushing"--contact forces at the macro level because of atoms not wanting to get to close at the micro level. Now we'll deal with "pulling" force or tension (at a micro level this is the force of attraction between bonded atoms).