Question

the iron Rim of a cartwheel is made slightly smaller than the wooden wheel and fixed and it after heating the rim strongly.

Answer 1

Metals have tendency of expanding on giving heat and contracting on cooling . A iron rim of a wooden wheel is made slightly smaller because when it is heated before fitting on to the wheel it expands . When it is fitted on to the wheel and allowed to cool the iron contracts and fits perfectly on to the rim of the wheel .

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