A. Flowing water and wind in nature are natural resources with a large amount of mechanical energy that can be used by humans by converting it into electrical energy, so A is correct; B. The hydraulic turbine drives the generator to turn water into water. Mechanical energy is converted to electrical energy, so B is correct
C. The steering wheel of an automobile is a common wheel axle, and its wheel; the radius is larger than the axle radius, which can save labor, so C is correct
D. The essence of the fixed pulley is an equal arm lever, which can change the direction of force without economy or effort, so D is wrong.
So choose D.
After comparing the three, the disadvantages are:
1. Solar energy is affected by rainy days (cannot continue to generate electricity when there is no light)
Wind energy is affectede by climate (when air cannot form convection, it cannot continue to produce electricity)
Hydraulic energy is affected by the flow of water (it cannot continue to produce electricity during dry seasons)
Based on the above, the three are mutually exclusive. The difference is that,
From a sequential point of view: solar energy is the most primitive energy, followed by wind energy and water (the potential energy of wind and water is not as good as the sun); p>From a distribution point of view: everywhere yes; water is not as good as sun and wind
From a collection point of view: build a dam that will have a long lifespan and can also store water for agriculture, so it can be used for many purposes. Sun and wind are not as good as water
From the point of view of practical use: onceonce a family has the equipment, it will become a river. Water is not as good as sun and wind
From the point of view of environmental protection and energy saving: water, the construction of dams transforms nature; the sun and wind do not directly affect nature;