REALLY need HELP to solve the problem

i have done an experiment to find the force of friction on several surfaces.but i found that the wooden block used can move in a smaller frictional force than on plastic or glass
Will the frictional force be smaller when the same material is used(wood on wood)?but there are many crests on wood, when the wooden block moves, crests will hit crests and make the block more difficult to move.
i suppose the frictiional force(wood on glass or plastic)is smaller then that of wood on wood


Staff Emeritus
Science Advisor
Gold Member
It is not clear to me, what your question is.


Science Advisor
Your only "problem" seems to be whether to trust your results. I would consider it very bad science to refuse to accept the results of an experiment because of some notion of what "should" happen.
need help with hw plzz help

al right the problem is (If u use a horizontalforce of 30.0N to slide a 12.0-kg wooden crate across a flor at a constant velocity, what is the coefficient of kinetic friction between the crate and the floor?) PLz help answr fast its due tmrw ahhhhh!

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