【判断题】In the event of a major tube failure of fire tube boiler,
high-pressure water can be forced directly into the furnace area,
rapidly creating large quantities of steam, which have the potential for
...
【简答题】某游乐场有一种叫“空中飞椅”的游乐设施,其基本装置是将绳子上端固定在转盘的边缘上,绳子下端连接座椅,人坐在座椅上随转盘旋转而在空中飞旋.若将人和座椅看成是一个质点,则可简化为如图所示的物理模型,其中 P 为处于水平面内的转盘,可绕竖直转轴 OO ′转动,设绳长 l = 10 m ,质点的质量 m = 60 kg ,转盘静止时质点与转轴之间的距离 d = 4 m .转盘逐渐加速转动,经过一段时间后质...