expansion of a disc

consider a metal disc with a hole in the centre.
when the disc is heated will the radius of the hole at centre increase or decrease?

2 Answers

it increases... and coefficient of expansion is same as that of the metal! [1]

wont the metal of the disc expand inwards like this??

then the radius will decrease??? am i wrong?

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∑ ∑ ∑ ∑ ∑ ∮ ∮ ∮ ∮ ∮ ∏ ∏ ∏ ∏ ∏ ∐ ∐ ∐ ∐ ∐

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