物理問題,about heat

No. This has nothing to do with radiation.
The boiling water in the pot always maintains a temperature of 100 deg.C, as there is no temperature change during a change of state. The heat supplied to the boiling water goes to the latent heat of water.
Under such situation, the water in the aluminium can is also kept at a temperature of 100 deg.C because aluminium is a good thermal conductor.
Heat could flow to the water in the aluminium can if there is a temperature difference. Now, the temperature of water in the aluminium can and that in the boiling water in the pot are the same. Without any temperature difference, heat stops to flow into the water in the can. Since latent heat is needed for water to boil, there is no extra heat given to the water in the can for it to boil.

這是因為水若要煲滾要到達攝氏100°.

放左個鋁罐后熱能被鋁罐迅速帶走.所以水很難到達攝氏100°