Final answer:
A bottle top is an example of a screw, which is a simple machine that transforms rotational motion into linear motion. It matches the definition of a screw due to its spiral thread that secures to a bottle's neck. Therefore, the correct option in the final answer is B. A bottle top.
Step-by-step explanation:
An example of a screw is a device that typically converts rotational motion into linear motion and is characterized by a spiral ridge or thread. The options presented include various items, but the one that aligns with the definition of a screw is B. A bottle top. A bottle top features a helical ridgeline that screws onto the thread of the bottle neck, securing the contents within.
In terms of physics, screws are considered simple machines. They are essentially inclined planes wrapped around a cylinder. This form allows for movement or the exertion of force with less effort over a longer distance or time. When you twist a bottle top, you are applying a rotational force that travels down the threads, effectively creating a linear motion that either seals or opens the bottle.
We encounter various types of screws in everyday life. From wood screws to screws used in machinery, they often require a tool (like a screwdriver) to apply the necessary torque. Screws are made of different types of metals and are designed for specific applications, such as fastening objects or hanging items on walls.
Therefore, the correct option in the final answer is B. A bottle top.