Wedge
A roof is not a simple machine. It is a structure built to provide shelter and protection from the elements.
A pin is classified as a type of fastener and not a simple machine. It is often used to secure two materials together.
A tack is a type of wedge, which is a simple machine that is used to push things apart or hold things together.
A projector screen is a type of lever simple machine when it is manually pulled down or rolled up. It can also be considered a pulley simple machine if it is motorized to retract or extend the screen.
If you think about this, you can figure it out. What shape is a shark's tooth? It's a triangle, right? What machine is a triangle shape? The only simple machine that looks like a triangle is a wedge.
Wedge
It is a simple lever mechanism using to hold round objects firmly without slipping, as well as to tighten square, hexagonal nuts or bolts.
A pulley isn't a kind of simple machine, it is a simple machine
A train is not a simple machine.
The jaw can be considered a simple machine in the sense that it functions like a lever. The jaw acts as a lever arm, with the hinge (the temporomandibular joint) serving as the fulcrum. When muscles contract to close the jaw, they exert force that allows for efficient biting and grinding of food, similar to how a lever amplifies force. However, it's important to note that the jaw's complexity and the involvement of various muscles and anatomical structures also add functional intricacies beyond a basic simple machine.
IT's NOT A SIMPLE MACHINE!
its not a simple machine
It is a simple lever.
Rope is not a simple machine on its own, it's a simple machine on a wheel and axle, then it's a pulley.
a compound machine is a combination of simple machines
lever
lever