Final answer:
The flow of air over the exposed rotor surfaces in wind turbines is channeled through the blades, which act like long airplane wings and can be rotated to engage the wind at different angles. The shape of the rotor creates a cylinder of air that encounters the blades. The blades play a crucial role in directing and controlling the air flow for effective wind energy harnessing.
Step-by-step explanation:
In wind turbines, the flow of air over the exposed rotor surfaces is channeled through the blades. The blades act like long airplane wings and are mounted on an axis so that they can be rotated and engage the wind at different angles, thus varying efficiency.
The shape of the rotor creates a volume of air that encounters the blades. This volume of air has the shape of a cylinder with a circular base area and a height that depends on the wind speed.
Overall, the blades play a crucial role in directing and controlling the flow of air over the rotor surfaces, allowing the wind energy to be harnessed effectively.