When we want to drink some hot water, we will use a hot water kettle to boil a pot, but have you ever thought about how to let the hot water that you can’t finish drinking slowly cool down? Isn't it a bit wasteful? A German design team designed an electromagnetic heating rod. If you put it in a glass of cold water, it will automatically identify the material and heat the water. It won't take long to drink a glass of warm water or milk. Simply touch the heating rod to the base to stop it.
