🪂 自由落体计算器Free Fall Calculator

使用说明与常见问题How-to & FAQ

「自由落体计算器」是什么？What is the Free Fall Calculator tool?

在忽略空气阻力的条件下，由下落高度、时间或末速度中的任意一个求出另外两个，可选择地球、月球、火星等重力加速度，并可设置初速度。Ignoring air resistance, give any one of fall height, time or final speed and get the other two, with Earth, Moon or Mars gravity and an optional initial downward speed.

如何使用「自由落体计算器」？How do I use the Free Fall Calculator tool?

在「自由落体计算器」中，填写「已知」、「数值（m、s 或 m/s）」、「初速度（向下，m/s）」、「重力」等参数，结果会随输入实时计算并显示在下方。In the Free Fall Calculator: Fill in "Known", "Value (m, s or m/s)", "Initial speed (downward, m/s)", "Gravity"; results are recalculated instantly as you type.

自由落体公式？Free-fall equations?

h = v₀t + ½gt²，v = v₀ + gt，v² = v₀² + 2gh。地球标准重力 g = 9.80665 m/s²。h = v₀t + ½gt², v = v₀ + gt and v² = v₀² + 2gh, with standard Earth gravity g = 9.80665 m/s².

考虑空气阻力吗？Does it include air resistance?

不考虑。现实中物体会趋于终端速度（常被引用的数字是：俯身姿势的跳伞者约 50–55 m/s，仅作粗略参考），下落距离较大时结果会偏大。No. Real objects approach a terminal velocity (a commonly quoted rough figure is about 50–55 m/s for a belly-down skydiver), so long falls are overestimated.

计算结果可以用于作业或工程吗？Can I use the results for homework or engineering?

「自由落体计算器」使用教科书标准公式（公式写在说明和常见问题中），适合学习和估算核对；涉及安全的工程设计请以规范和实测为准。The Free Fall Calculator uses standard textbook formulas (given in the description and FAQ), which is good for learning and checking estimates; for safety-critical engineering follow codes and measured values.

「自由落体计算器」免费吗？需要注册吗？Is the Free Fall Calculator free? Do I need an account?

「自由落体计算器」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Free Fall Calculator is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.