Archer gets ready to make his mark.

From "Matter and Energy", John Clark, 1994

Fresh water running back to its source.

Which force is pulling the water down?

1: GRAVITY Mass is a measure of the quantity of matter. Imagine from the center of the Earth coming a mighty ladder. Gravity depends on the distance from an object’s center you see, Constructing heavenly bodies that are spherical shaped most naturally . Gravity also depends on an object’s mass and density, Which is why black holes have awesome gravitational propensity. Are you drawn vertically down to the center of mass? Or should you let this interesting opportunity quickly pass? You don’t fly into space because of gravity, Partly because of the planet's mass and density. But also due to our distance from the sun, Which is why we orbit; due to sun and earth’s attraction. The moon’s gravity changes the ocean’s tides. Do you still think you can from gravity hide? The center of an object and the surface of an object. Two particles communicating in a most strange dialect. Proportional to their masses and inversely to their distance, Or in plainspoken language, they just want to hug and dance.

2: HYDRAULICS When you squeeze a liquid down, it will never compress, Hydraulics is based on this fascinating premise. Squeeze a tube of toothpaste and the paste will come out, Whether you squeeze it high or low or anywhere about. You’ve just shown yourself how hydraulics works. Listen how this force is used in a fortuitous quirk. A water gun is an example of hydraulics in use, But this force can be harnessed in a more miraculous ruse, Like bulldozers, airplane rudders and hydraulic jacks, The ability to move big things where our muscles would lack. It’s based on a small force activating a much larger one. The force is based on liquid oil compression by a piston(1). When a control lever pushes a small piston down, The hydraulic oil supply is squeezed equally around. The squeezed out oil is pushed into a larger cylinder(2), Which activates a piston, which gives a force much bigger. That’s how one person can lift up a monstrous truck. It’s an awesome discovery working much to our luck. 1: Piston-A sliding metal cylinder either by fluid (liquid) or gaseous pressure. 2: Cylinder-A device that converts hydraulic (liquid) or gaseous pressure into useful mechanical energy. An example would be the cylinders in your car converting the energy of the gasoline to movement of your car.

3: LEVERS I could move the world with a lever long enough, So said Archimedes in 200 BC and he really knew his stuff. Yes, the lever principle has been used for many many years, But many modern machines also use levers, thus decreasing our fear Of moving massive objects like draw bridges or cranes, From equalization of force do we much leverage gain. Scissors, see saws, corkscrews, construction cranes and so much more, All operate on the leverage principle right to their central core. Let’s start with a see saw which you do so much enjoy, And share one with your uncle who’s much bigger than a boy. You wonder how you’re to lift a man of a girth quite round, Whose rump seems quite firmly planted on the solid ground. But, alas, think leverage, and a solution can be found, And you’ll lift your big uncle, and soon be homeward bound. Ask you uncle to slide closer to the pivot(3) to balance out the force, While you slide further away, and, look, you’re now the boss. As you watch your uncle’s feet lift up and hang to the side, You’ve a balance of force, now sit back, enjoy the ride! 3: Pivot-The center or fulcrum of two equally opposing forces. Think see saw.

4: MAGNETS A magnet is a piece of metal which attracts, But do not think it cannot as well repel, For in opposites, the magnet surely does not lack, Listen, I’ve something interesting to tell. You see, every magnet has two opposite poles(4), And yes, these opposites play very important roles. Positive clicks with negative and vice versa, But listen carefully as I go a little further. With magnets, those similar poles are cast away, While with opposites, they’re known to hug all day. What makes this all happen you’re bound to say, I’ll need a bit of your time if that would be okay. The world is made of molecules and molecules of atoms, And atoms made of protons, neutrons and electrons(5). Now these electrons will generate a small magnetic charge. When these electrons work together, the effect can be quite large. To make a magnet work, you’ll need to line electrons up, Like you did in elementary school when you were still a pup. Now how to get electrons in parallel straight lines, While they prefer to burst about and say, “Thank you, we’re fine.” You’ll need a dash of electricity (5a) and a thimble full of luck, Or perhaps another magnet that already has its pluck. Magnets have many uses, way too numerous to list, But remember, opposites attract, like repel, is the central gist. 4: Poles-In this case, a positive and negative force. Remember, with magnets, opposite forces attract and like forces repel (push away). 5: Protons, neutrons and electrons-Subatomic particles forming the basis of atoms. The electrons in an atom have a negative charge and the protons have a positive charge. The number of electrons and protons in an atom are equal. Neutrons are neutral, that is, they have no charge, either positive or negative. 5a:  Magnetism is part of the electromagnetic force.  Electricity in motion creates magnetic fields and changing magnetic fields produces electricity so the two forces are irrevocably intertwined.

A demonstration of one of Newton's laws.

From "Matter and Energy", John Clark, 1994.

5: NEWTON’S THREE LAWS OF MOTION An equal and opposite reaction will encounter every force, And we witness this unerring truth in our daily course. For example, try hitting your desk with an open hand, Making you wish your desk was not made of wood but sand. You’ve just experienced opposing forces, one of Newton’s laws, Allow me to explain this further once you’re done nursing your paw. A football game demonstrates Newton’s first law of motion, That is; force is needed to move an object or change its direction. The recoil(6) felt by a rifleman when he shoots, Is a reaction to the bullet zinging from an explosive boot. These two forces are exactly equal, can’t you see, And dependent on the mass and an object’s velocity(7), Which is the speed of something in any given direction, And his second law states force equals mass times acceleration(8). When you think this over, it makes a lot of sense, Because a large truck hitting a car leaves a really big dent. In this case, the truck’s greater mass causes the damage and pain, But this law is also put to use much to our technological gain. All engines are based on Newton’s laws of motion, The next time you ride in a car, think over this notion.(9) Newton’s third law is very interesting and I do wish it were mine, That is, an object will always travel in a perfect line, Unless there’s an obstacle or a force deflects its course, That’s why a ball doesn’t go forever when you give it a toss. Can you tell me the name of that force that makes the ball come down? It’s the same force that keeps you planted on the solid ground. 6: Recoil-The rearward (backward) movement of a gun caused by the forward movement of the projectile. 7: Velocity-How fast an object moves or changes from a still position. 8: Acceleration-The change in velocity in relationship to measured time. 9:  Click "Newton and Autos" link below to find out how.

Newton's Three Laws of Motion and Automobiles.

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