Science
Forces & Motion
Conceptual
12–14 yrs
Moments, Pressure & Hooke's Law
力矩、压强与胡克定律
Description
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)
Mastery Evidence
- 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)
Assessment Prompt
If your child 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?
