The pole vault landing pad at an Olympic competition includes what is basically a bag of air which compresses from its "resting" height of 1.4 m down to 0.3 m as the vaulter is slowed to a stop.
(i) Determine the time interval throughout which a vaulter who has just cleared a height of 6.7 m slows to a stop?
(ii) Determine the time interval if rather the vaulter is brought to rest through a 21.8-cm layer of sawdust which compresses to 5.4 cm when he lands?
(iii) Qualitatively describe the difference in average force the vaulter experiences from the two various landing pads. That is, which landing pad would apply the least force on the vaulter and explain why?