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A man grows into a giant whose every linear dimension is multiplied by 9, his density remaining unchanged. By what factor does the compressive stress in his leg bones change?
- 81
- 1/81
- 9
- 1/9
Correct answer: 9
Solution
Stress ~ (rho L³ g)/L² = rho g L, so it scales linearly with L, i.e. by a factor of 9.
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