A blacksmith heated a metal whose cubic expansivity is 3.9 x 10\(^{-6}\)K\(^{-1}\). Calculate the area expansivity.
- 3.9 x 10\(^{-6}\)K\(^{-1}\)
-
2.6 x 10\(^{-6}\)K\(^{-1}\).
- 1.3 x 10\(^{-6}\)K\(^{-1}\).
- 1.6 x 10\(^{-6}\)K\(^{-1}\).
The correct answer is: B
Explanation
3\(\alpha\) = \(\gamma\)
\(\alpha\) = \(\frac{3.9\times 10^{-6}}{3}\) = 1.3 x 10\(^{-6}\)
BUT \(\beta\) = 2\(\alpha\)
\(\beta\) = 2 x 1.3 x 10\(^{-6}\) = 2.6 x 10\(^{-6}\)K\(^{-1}\)
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