Wedge
A wedge actually uses two inclined planes on either side of it to work. these inclined planes come together at a sharp edge that allows the wedge to cut in between what it is trying to split apart. The edge of an axe is very sharp because it needs to cut through the hard bark of tree trunks. Once it cuts into the tree, the inclined planes on either side of the axe do all the work! When force is applied to the wedge, the two inclined planes force the tree apart and eventually will split in half!
The arrow on the top of our picture shows the force being pushed down on the wedge. The two little arrows are also the force, but the ones acting on the wood. See how those arrows are smaller? That means that the big force we are using on the wedge is being split into two forces pulling the wood in opposite directions!
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