Concept explainers
A person jumps from a wall and lands stiff-legged. Which statement best explains why the person is less likely to be injured when landing on soft sand than on concrete?
a. The concrete can exert a greater force than the sand.
b. The person sinks into the sand, increasing the stopping distance.
c. The upward acceleration of the person in the sand is less than on concrete, thus the force that the dand exerts on the person is less.
d. b and c
e. a, b, and c
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