设细线的拉力为T,则有
Tsinθ=ma,Tcosθ+F=mg,F=kx
联立解得:x=m(g-acotθ)/k
讨论:
(1)若a<g/cotθ,则弹簧伸长x=m(g-acotθ)/k
(2)若a=g/cotθ,则弹簧伸长x=0
(3)若a>g/cotθ,则弹簧压缩x=m(acotθ-g)/k
设细线的拉力为T,则有
Tsinθ=ma,Tcosθ+F=mg,F=kx
联立解得:x=m(g-acotθ)/k
讨论:
(1)若a<g/cotθ,则弹簧伸长x=m(g-acotθ)/k
(2)若a=g/cotθ,则弹簧伸长x=0
(3)若a>g/cotθ,则弹簧压缩x=m(acotθ-g)/k