well, according to hookes law: strain in a solid is proportional to the applied stress within the elastic limit of that soid or material. according to your question Therubber bandactually expands when it gets colder! This seems counterintuitive because most materials expand when they are heated and contract when they get cold. This occurs because of the unusual polymer structure of rubber. whereas holy thread is normal material which contracts on being cold and expands while hot considering temperature of water to be ooler than room temperature