理论力学全套解疑 第13章.pdf

ma = ∑F O r 2 d r a dt 2 2 d r m 2 ∑F dt d2 x m 2 ∑Fx dt d2 y m 2 ∑Fy dt d2 z m 2 ∑Fz dt 2 dv d s maτ m m 2 ∑Fτ dt dt 2 2 v s man m m ∑Fn ρ ρ mab 0 ∑Fb ⎡ 2 2 ⎤ d r dϕ ⎛ ⎞ mar m⎢ 2 −r⎜ ⎟ ⎥ ∑Fr dt dt ⎢⎣ ⎝ ⎠ ⎦⎥ ⎡ d2ϕ dr dϕ⎤ maϕ m r −2 ∑Fϕ ⎢ 2 ⎥ ⎣ dt dt dt ⎦ r = r(t)x = x(t)y = y (t) z = z(t)s = s(t)