Why is metal rim heated before fixing on to wooden cart wheel?
Answers
A blacksmith heats the metal rim to fix it onto a cart wheel because a metal rim is made slightly smaller. On heating, the rim expands and fits onto the wheel. Then on cooling, the rim contracts and fits tightly onto the wheel.
Answer:
Explanation:
Metals expand on heating and contract on cooling. This expansion and contraction of a metal is a reversible change. The metallic rim used is slightly smaller in diameter than the wheels .On heating the rim expands. And can easily lie on the wheels. When the rim cools, it contract and press tightly on to the wheels. A blacksmith heats the metal rim to fix it onto a cart wheel because a metal rim is made slightly smaller. On heating, the rim expands and fits onto the wheel. Then on cooling, the rim contracts and fits tightly onto the wheel