A machine that is driven or powered by rotating blades to convert fluid flow or wind into useful mechanical or electrical energy is called a:

Introduction / Context:
Many modern energy systems use devices with rotating blades to capture energy from moving fluids such as water, steam, or air. These devices convert the kinetic or potential energy of the fluid into mechanical rotation, which can then be used to generate electricity or drive machinery. This question asks you to identify the correct technical term for a machine that is powered by rotating blades in this way.

Given Data / Assumptions:

• The machine operates with rotating blades driven by a fluid such as water, steam, gas, or wind.
• The context includes hydroelectric, steam, gas, and wind power applications.
• Options include fumarole, turbine, solar panel, and none of the above.
• We assume standard definitions of energy conversion devices.

Concept / Approach:
A turbine is a machine with a rotor and blades designed so that a moving fluid imparts torque, causing rotation. This rotation can directly drive mechanical loads or be coupled to an electric generator to produce electricity. Different types include steam turbines in power plants, gas turbines in jet engines, water turbines in hydroelectric dams, and wind turbines that convert wind energy into electrical power. A fumarole is a natural steam vent in volcanic areas, not a machine. A solar panel converts sunlight into electricity using photovoltaic cells and has no rotating blades. Therefore, the correct term for a machine powered by rotating blades is turbine.

Step-by-Step Solution:
Step 1: Identify the key features in the description: a machine, rotating blades, and conversion of flow energy into useful output. Step 2: Recall that a turbine is specifically designed to extract energy from a fluid stream using blades fixed to a rotor. Step 3: Connect common examples such as wind turbines, steam turbines, and water turbines, all of which fit the description given. Step 4: Compare this with a solar panel, which relies on semiconductor materials and sunlight, not rotating blades or fluids. Step 5: Conclude that the machine described is most accurately called a turbine.

Verification / Alternative check:
Descriptions of power plants frequently mention steam turbines driven by high pressure steam from boilers, gas turbines driven by burning fuel and compressed air, and water turbines turned by flowing water in dams. Wind farms are built with many large wind turbines whose blades are rotated by the wind to generate electricity. In each case, the term turbine is used for the blade based machine. Fumaroles are recorded in geology texts as natural volcanic vents, and solar panels appear in renewable energy discussions as flat modules, confirming that neither of these matches the rotating blade description.

Why Other Options Are Wrong:
Fumarole: A fumarole is a natural opening in the Earth crust that emits steam and gases; it is not a man made machine with blades. Solar panel: A solar panel converts sunlight directly into electricity using photovoltaic cells and has no rotating blades or fluid driven rotors. None of the above: Incorrect because turbine precisely fits the description of a machine powered by rotating blades.

Common Pitfalls:
Students may sometimes confuse different renewable energy devices if they focus only on the power source, such as sun or wind, and not on how the energy is converted. Remember that turbines always involve rotating blades and a moving fluid, whereas solar panels are static devices relying on light and semiconductors. Keeping these physical differences in mind helps in identifying the correct terminology in exam questions.

Final Answer:
A machine powered by rotating blades to convert fluid or wind energy into useful output is called a turbine.