质点沿直线运动,初速V0,加速度a=-k√V,K为正常数dv/dt=-k√V dv/√V =-kdt得√V=√V0 - kt/2质点完全静止v=0所需时间 t=(2√Vo )/k√V=√Vo - kt/2 dx/4t=V=Vo-kt√Vo+k²t²/4 x(t)=Vot-2k√Vot²+k&su...