物理摩擦力--看得懂英文的进!A41kgboxrestsonalevelsurface.Thecoefficientofstaticfriction,μS=1.1andthecoefficientofkineticfriction,μK=0.7.求：F(gravity)onboxfromsurfaceFNormalonboxfromEarthFfrictiononbox

　　物理摩擦力--看得懂英文的进!

　　A41kgboxrestsonalevelsurface.Thecoefficientofstaticfriction,μS=1.1andthecoefficientofkineticfriction,μK=0.7.

　　求：F(gravity)onboxfromsurface

　　FNormalonboxfromEarth

　　Ffrictiononboxfromsurface

　　请大大解释coefficientofstaticfriction和coefficientofkineticfriction到底是什么意思(那个东西没有动为什么会有kineticfriction),然后Fnormal,Fgravity和Ffriction的意思.

　　最后..请不要上网给我那些单字的长篇资料,我是查过看不懂以后才来的!