We all know that if we fall out of a bunk bed we will fall to the floor. Or if we jump off a rocky cliff, we better make sure there is water below for us to fall into. From infancy we have been playing with gravity. What goes up, must come down. Do we really understand why? 1. Star Wars' Obi-Wan Kenobi said the Force “surrounds us and penetrates us; it binds the galaxy together.” He could have been talking about gravity. Its attractive properties literally bind the galaxy together, but it also “penetrates” us, extending physically through us, keeping us bound to Earth. 2. Unlike the Force, with its dark and light sides, gravity has no duality; it only attracts, never repels. 3. Passengers on amusement park rides and the International Space Station experience microgravity — incorrectly known as zero gravity — because they fall at the same speed as the vehicles. 4. Someone who weighs 150 pounds on Earth would — if it were possible to stand on Jupiter — weigh a whopping 354 pounds on the enormous gas giant. Larger masses have greater gravity. 5. To leave Earth’s gravitational pull behind, an object must travel 7 miles a second, our planet’s escape velocity. 6. Gravity is by far the weakest of the four fundamental forces. The other three are electromagnetism; weak nuclear force, which governs how atoms decay; and strong nuclear force, which holds atomic nuclei together. 7. A dime-size magnet has enough electromagnetic force to overcome all of Earth’s gravity and stick to the fridge. 8. An apple didn't hit Isaac Newton in the head, but it did make him wonder if the force that makes apples fall influences the moon’s motion around Earth. 9. Gravity’s inverse square law also means the reach of gravitational attraction is technically infinite. Whoa. 10. Gravity’s other definition — meaning something weighty or serious — came first, originating from the Latin gravis, or “heavy.” Tired? It could be gravity pushing on you all day?
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Mrs. TaylorI love science! Everything about the world is interesting and never boring. I love to study plants, animals, insects, and people. My favorite subjects are my students who are the most unique organisms on the planet! Categories |