This particular simple machine is a lever. I know it's really a bottle opener, but it is a lever cleverly disguised as a bottle opener. When most people think of a lever they think of a balance beam or a board that is wedged under something that needs to be moved with a rock for support in the middle and the opposite end is pressed down or see-saws. Those are levers, but they are only one of three type of levers. Those examples show a 1st class lever where there is a support somewhere in the middle of the board with the thing to be lifted (load) on one side and the other side is where we try to make the board move (force).
In a 2nd class lever, as shown above, the fulcrum (support point) is not between the load (what needs to be moved) and the force (the lifting or pressing). A 2nd class lever has the load between the fulcrum and the force. As shown in the photo, the fulcrum is the end if the bottle opener that rests on the bottle cap. The load is the edge of the bottle lid that needs to be lifted. The force is the hand that lifts the other end of the bottle opener.
Now, if you buy that extra tasty rootbeer or cream soda in the fancy glass bottles, the kids will love to hear about 2nd class levers while opening their drinks. Or, if you are like me, you teach the children about 2nd class levers so that when you ask them to fetch you a drink, they can open it for you too.
Here is a link that has more explanation and examples of levers.
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