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प्रश्न
Give a reason why iron objects rust easily but the iron pillar at Qutab Minar has not rusted over the years.
उत्तर
The iron pillar at Qutab Minar has not rusted for 1600 years because of the following reasons:
- The high purity and great mass of iron may have created a temperature stabilizer thus reducing the condensation of moisture on it.
- The protective scale or passive iron coating formation on the surface, better forge welding and absence of impurities in iron – also may have dissuaded corrosion.
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