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## Homework Statement

Two different materials are being considered for a safety pad below a swing. Material 1 has a Young's Modulus twice that of Material 2. Which should be chosen?

A. Material 2, because the length over which the impact force acts is larger, resulting in a lower average impact force.

B. Material 1, because the length over which the impact force acts is larger, resulting in a lower average impact force.

C. Material 2, because a material with a lower Young's Modulus will absorb kinetic energy more quickly.

D. Material 1, because a material with a higher Young's Modulus will absorb kinetic energy more quickly.

## Homework Equations

([tex]\Delta[/tex]L/L

_{o})*E=F/A.

## The Attempt at a Solution

[tex]\Delta[/tex]L is clearly larger with a smaller YM, but does the mean the length over which the impact force acts is larger. Does that then mean that it's lower impact? I've never even come across the idea of absorption of kinetic energy, and I don't think it's obvious that something that is "squishy" should absorb kinetic energy more quickly...