Elevator Problem

电梯问题

This is an application of Newton's second law to the forces felt in an elevator. If you are accelerating upward you feel heavier, and if you are accelerating downward you feel lighter. If the elevator cable broke, you would feel weightless since both you and the elevator would be accelerating downward at the same rate.

这是牛顿第二定律应用于电梯中感受到的力的情况。如果你向上加速，你会感觉更重；如果你向下加速，你会感觉更轻。如果电梯的钢索断裂，你将感觉失重，因为你和电梯将以相同的速度向下加速。

support force F = mass x acceleration + weight

支撑力 F = 质量 × 加速度 + 重量

See lifting mass problem

见提升质量问题

对于质量为 m=kg 的物体，电梯必须支撑其重量 = mg = 牛顿以使其静止不动。如果加速度是 a= m/s²，那么需要一个净力=牛顿来加速该质量。这需要支撑力为 F=牛顿。请注意，当加速度为零时，支撑力等于重量；如果加速度为负（向下），支撑力将小于重量。如果你进入大于 9.8 m/s² 的向下加速度，将得到负的支撑力，这表明你必须强制向下加速以获得比自由落体加速度更大的加速度。

中文译文中的待填/计算数值依次对应：1：m 2：w 3：ac 4：nf 5：t。实际数值以上方原输入框为准。

You Feel "Weightless" If the Elevator Cable Breaks

如果你电梯的钢索断裂，你会感觉失重

The phenomenon of "weightlessness" occurs when there is no force of support on your body. When your body is effectively in "free fall", accelerating downward at the acceleration of gravity, then you are not being supported. The sensation of apparent weight comes from the support that you feel from the floor, from a chair, etc. Different sensations of apparent weight can occur on an elevator since it is capable of zero or constant speed (zero acceleration) and can accelerate either upward or downward. If the elevator cable breaks then both you and the elevator are in free fall. The resultant experience of weightlessness might be exhilirating if it weren't for the anticipation of the quick stop at the bottom.

‘失重’现象发生在身体没有支撑力作用时。当你的身体有效地处于‘自由下落’状态，以重力加速度向下加速时，你就不会受到支撑。你感受到的‘ apparent weight ’来自你从地面、椅子等感受到的支撑力。电梯中可以产生不同的‘ apparent weight ’感觉，因为电梯可以有零或恒定的速度（零加速度），也可以向上或向下加速。如果电梯的钢索断裂，你和电梯都会处于自由下落状态。这种失重体验可能会令人兴奋，但如果没有快速停止的预期，这种体验可能会让人感到不安。