What is a compound machine?

A compound machine is defined as a combination of two or more simple machines working together to perform a specific function or task. Simple machines, such as levers, pulleys, wheels and axles, inclined planes, screws, and wedges, often serve as the building blocks for these more complex systems. By utilizing the advantages of multiple simple machines, a compound machine can achieve greater mechanical advantage or efficiency in performing work.

Understanding compound machines is essential as they are frequently found in everyday tools and devices, such as bicycles, cranes, and even some kitchen appliances. They combine the functionality and efficiency of simple machines, allowing for tasks to be accomplished with less effort or in more effective ways.

The other options do not accurately describe a compound machine. A single simple machine does not meet the criteria of being a compound machine, nor does a machine that cannot be dismantled or a complex device that requires electricity. These definitions focus on characteristics that are not relevant to the essential nature of what constitutes a compound machine.