Topics to revise
Forces & Elasticity P2
Homeostasis & Hormones P2
Required practical - Hooke's Law & Elasticity
2026 - Next week is Wave 2 mocks - if you can get ahead, it will help later.
Checklist
Mind map
Force and Extension
Investigate the relationship between force and extension for a spring.
Check your understanding with these quick common questions. Use the drop down boxes to see the correct answers.
Forces & Extension
When a force (weight) is added to a spring, it stretches. Many springs will follow Hooke's law, which says that if you double the force pulling the spring, is you will double how far it extends. This applies to the limit of proportionality. This is the point when the spring does not spring back. The spring constant can be calculated if you measure the force and extension. This is how stiff the spring is.
Independent variable: Force (weight added).
Dependent variable: Extension of the spring.
Control variables (3): Same spring; measuring from the same zero mark;
Clamp stand
Ruler to measure extension
Weights (yes weights not masses as we are mesuring the force not mass)
Accuracy can be improved by: Ensuring you clamp the ruler so your hand does not wobble.
Read the ruler at eye level to avoid Parallax error
Other improvements: Repeat and calculate a mean.
The graph should show a directly proportional relationship
Hang a spring from a clamp
Fix a ruler alongside the spring
Record the ruler reading at bottom of the spring
Hang a weight and record the new position on the ruler
Measure the extension in meters
Change the weight - use at least 5 different weights
Plot a graph of Force (X) and Extension (Y)
Calculate the gradient to find the spring constant