Okay… GED science pop-quiz time!!! Here’s a practice question jus’ like you might get on any GED science test… Say you want to move a giant happy face. You know, like you’re making a big sign for your new club, called “Be Happy!” and it’s a huge yellow happy-face guy. But you gotta lift it up onto the truck to get it to your club. Kewl. Okay, here’s where the GED science comes in… You got your choice of two levers (simple machines!!) to pick up the sign… here they are…
Which one’s gonna be easier? Cuz, that’s the important thing. No one wants to work too hard, right? So, work smarter! Pick the easiest lever! Do it!
A) Lever A
B) Lever B
C) Both are the same.
You got your answer? Choose one now! Cuz I’m gonna explain it in a minute….
I’m waiting. You answered the question yet?
Oh, okay. Here’s the answer… it’s… Lever B!!! Yes, answer B is correct. Did you get it right? Here’s why… and it’s pretty important to know for the test…
The amount of work you’re doin’ is equal to the amount of force you put on the lever (how hard you push down) times the distance from the fulcrum (that’s the triangle in the center!). So, the further away you are from the fulcrum, the more you’re adding to your force to do more work! Cuz you multiply it by the distance, the farther away you get from the fulcrum, the more distance you got, and the more work you do.
Same thing with the other side. You want to put your happy face as close to the fulcrum as possible, because it’s like you multiply how heavy it is by the distance from the fulcrum to figure out how much you gotta lift. It’s pushing down on the lever, right? You gotta push down harder to lift it. So you want its “pushing down”ness to be as small as possible (as close as you can get it to the fulcrum.) And, you want your “pushing down”ness to be as big as possible (as far as you can get from the fulcrum). Get it?
Try this at home. Like, you can make a scale by tying a string in the center of a stick and hanging it from the ceiling. It’s just like a lever, but the fulcrum’s holding it up instead of on the bottom. Get it? Now, you can tie different things to each side to see which one’s heaviest. Try tying two identical things (like matching earrings) to the scale. If they’re the same distance from the center (fulcrum) the scale should balance.
If one’s farther away than the other, it pulls its side down. It’s like it’s heavier! That’s cuz the distance, not just the weight, is part of how it affects the lever. Kewl. Play around with it… that’s the best way to understand it, I think.
Happy GED learning!
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