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Why does the lid come off when you use a blender with hot liquid but it doesn’t come off when you use it with cold liquid? Help me explain to my friend why it’s safer to let the steam come out and not over full the blender with hot soup.
In: 20
Surface area, heat, and expansion.
When the blender is half full of hot water, and half air, the surface area is small, and the air temperature only slowly rises from the hot water. Once you hit blend, the surface area of the water and air is increase thousands of times, now the water can swiftly share that heat with the air, causing it to expand, and the lid blowing off.
The opposite can be done with cold water, and have the lid suck in.
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