U is inversely proportional to the cube of V and U = 81 when V…

Explanation

U \(\propto \frac{1}{V^3}\)

U = \(\frac{k}{V^3}\)

k = UV\(^3\)

k = 81 x 2\(^3\) = 81 x 8

When V = 3,

U = \(\frac{k}{V^3}\)

U = \(\frac{81 \times 8}{3^3}\)

U = \(\frac{81 \times 8}{27}\) = 24

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