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Anonymous users2024-01-24A. Sitting on a sofa is more comfortable than sitting on a wooden stool, which is used to reduce the pressure by increasing the force area under a certain pressure, so this option is wrong;
B. Sharpen the knife before cutting the meat, in order to increase the pressure by reducing the force area under the same pressure, so this option is wrong;
C. It is easy to push a few round wooden sticks under the wooden box, because the rolling friction is smaller than the sliding friction, so this option is wrong;
D. The purpose of the maglev train is: to reduce the friction between the car and the track, and to increase the speed of the car Therefore, the magnetic pole of the same name is used to repel each other, so that the train leaves the track slightly and reduces the friction, so this option is correct
So choose D
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