力矩、压强与胡克定律
Moments, Pressure & Hooke's Law
计算力产生的转动效果（力矩 = 力 × 垂直距离），解释液体中压强如何等量传递（帕斯卡原理）和大气压强的概念，并描述胡克定律（在弹性限度内，伸长量与力成正比）。
Calculate the turning effect (moment = force × perpendicular distance), explain how pressure is transmitted equally in liquids (Pascal's principle) and the concept of atmospheric pressure, and describe Hooke's Law (extension ∝ force up to the elastic limit)
学习证据 / Evidence
- 计算力的力矩，并运用力矩原理解决杠杆问题。
- 解释液压系统为什么能放大作用力（因为压强等量传递）。
- 陈述胡克定律，并绘制力-伸长量图像，标出弹性限度。
- 根据力-伸长量图像计算弹簧的劲度系数 k（k = F/x）。
- Calculates the moment of a force and uses the principle of moments to solve lever problems
- Explains why hydraulic systems can multiply force (pressure transmitted equally)
- States Hooke's Law and plots force-extension graphs identifying the elastic limit
- Calculates spring constant k from a force-extension graph (k = F/x)
评估问题 / Assessment
如果{{name}}用一把长扳手去拧松一个很紧的螺栓，{{name}}能解释为什么用较长的扳手会更容易拧松，并算出用特定长度的扳手时需要的力有多大吗？
If {{name}} was using a long spanner to loosen a tight bolt, could they explain why a longer spanner makes it easier — and work out what force would be needed with a spanner of a specific length?