由能量守恒,子弹动能转化为弹簧弹性势能和克服摩擦力做功f=8.98*10*0.2=17.96W摩擦=f*s=17.96*0.1=1.796J弹性势能=100*0.01/2=0.5Jv=(2.296*2/0.02)开根号
能量守恒,得:1/2*(m+M)v1^2=u(M+m)gS+1/2*kS^29/2*v1^2=0.2*9*10*0.1+1/2*100*0.01v1^2=1/2v1=(根号2)/2mv=(m+M)v1v=[9*(根号2)/2]/0.02=225根号2m/s