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Is the buoyancy of a 5N object floating on the water equal to or greater than 5N Wu
be equal to
The floating object must be balanced in the vertical direction,
Buoyancy is equal to gravity
When cleaning the blackboard, what is the friction between the eraser and the blackboard surface?
Static friction or sliding friction? Why?
There is relative motion Sliding friction
When cleaning the blackboard, the friction between the blackboard eraser and the blackboard surface is very small______ Friction: when people walk, the friction between the sole and the ground is very small______ Friction. When riding a bicycle, what is the friction between the wheel and the ground______ Friction
There is sliding between the blackboard eraser and the blackboard surface, so the friction between the two is sliding friction. When people walk, there is a relative movement trend between the sole and the ground, but they do not slide on the surface, so the friction between the two is static friction. When riding, the wheel rolls on the ground, so the friction between the wheel and the ground belongs to rolling friction Static; rolling
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