1.3 (b)
Contents
Class Experiment
The pupils should measure force-extension data for both springs and elastic bands.
Resources
Analysis
Plot force-extension graphs and discuss the relevance of the gradient (stiffness) and area under the graph (work done).
Equipment
20x 100g masses and hangers, 1x spring, 1x elastic band, 1x ruler, 1x stand, boss head and clamp
Safety
Safety goggles should be warn at all times during the experiment
Class Experiment
Bungee jump. The pupils have to predict how high to set a bungee jump for a 100g mass or toy figure (depending on the elasticity of the elastic). They need to measure force-extension data for the elastic. Using this information you calculate the elastic energy of the elastic at different xtensions.
Resources
Analysis
Plot an Energy-extension graph. First of all you plot a curve of elastic energy stord against extension. Then on the same axes you plot GPE lost against extension. Where the two lines cross the GPE lost = elastic p.e. gained and the figure or mass will stop falling. Knowing the original length of the rope and this extension will give you the height to set the jump so that the figure will only just get its head submerged in the 'river'.
Equipment
20x 100g masses and hangers, 1x stand, boss head and clamp, 1x ruler, 1x elastic thread
Safety
Safety goggles should be warn at all times during the experiment
