Do you want to be Robin's friend? 你想成为Robin的朋友吗?试着给Robin写封信吧!
Dear Robin,
I want to be your friend. I am a ____. I'm ____ years old. I can ____.I can ____. But I can't ____. Can I be your friend? Please tell me! Thank you.
____
如图所示,质量m=2kg的金属块(可视为质点)静止于水平平台上的A点,金属块与平台之间动摩擦因数为0.5.现施加一与水平方向成θ=37°角斜向上、大小为F=20N的拉力,作用2s后撤去,物体继续在平台上滑行一段距离后停止,(cos37°=0.8,sin37°=0.6,g=10m/s2)求: