如图所示,一长平板车,在 t = 0 时从静止开始以 (SI)作加速直线运动。车上一质量 m = 5 kg 的物体位于车前 A 位置处,t = 0 时,物体开始滑动,物体与平板车间的滑动摩擦系数为 μ = 0.15。则经过 2 s 时间,物体在车上滑移的距离为 m。(重力加速度 g 取 10 m/s 2 )
【单选题】听力原文: One day, Mr. Lock received a visit from a salesman representing Bargain Electrics Ltd, who persuaded him to buy an electric drill for $ 60. He told Mr. Lock that if he sent a $15 deposit, they c...