Question

why cold water is poured over hot metal rim which covers a wooden wheel​

Answer 1

Answer:

The metal rim is made slightly smaller than the wooden wheel. On heating, the rim expands and fits onto the wheel. Cold water is then poured over the rim, which contracts and fits tightly onto the wheel.

Answer 2

Answer:

Cold water is then poured over rim, which contracts and fits tightly onto the wheel.

Explanation:

The metal rim is made slightly smaller than the wooden wheel. On heating, the rim expands and fits onto the wheel. Cold water is then poured over the rim, which contracts and fits tightly onto the wheel.