5. A car of mass m moving at a speed \( v_1 \) collides and couples with the back of a truck of mass 2m moving initially in the same direction as the car at a lower speed \( v_2 \). What is the speed \( v_f \) of the two vehicles immediately after the collision?
(A)\( v_f = \frac{2}{3}(v_1 - 2v_2) \)
(B)\( v_f = \frac{2}{3}(v_1 + v_2) \)
(C)\( v_f = \frac{1}{3}(v_1 - 2v_2) \)
(D)\( v_f = \frac{1}{3}(v_1 + 2v_2) \)
(E)\( v_f = \frac{1}{2}(v_1 + v_2) \)
答案:登入後查看
統計: 尚無統計資料
統計: 尚無統計資料