A man in this clip give two objects to people and ask them “How do you feel ?”. All people who touch objects between book and metal. They are feel metal colder than a book even if there are same temperature. Also the second experiment, when you lay down an ice on a plastic plate and aluminium plate. The ice whice on aluminium melt faster than the ice on plastic. Because this is about thermoconductivity, the rate at which heat is transferred from one object to another. The ice on aluminium plate melt faster because aluminium plate is conducting the heat to the ice faster. The plastic plate is a worse thermoconductor. So heat is being transferred less quickly to this ice and it’s melt slowly like the first experiment. You felt metal colder than book because metal conducts heat away from your hands faster than the book.