Recent content by oliviecheng

a bucket of water is tied to a string and spun in a circle, why don’t the water spill out?can somebody help me explain detailly? thx a lot

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...