1001 Space Earth Nature History Human World Science and Technology Chemistry Materials Force and Energy Heat and Light Electricity and Magnetism Industry Machines Electronics and Computers Cars and Trucks Railways Ships Aircraft Fishing and Agriculture Undersea Exploration

Choose a Page:What happens when colours are mixed?How does the Sun produce light?What is light?*How does a vacuum flask work?*What is heat?What is colour?How does heat travel?What is temperature?How do thermometers work?What is the coldest possible tempe...How fast does light travel?How do our eyes detect light?How do glasses work? How does a vacuum flask work? Because heat cannot travel through a vacuum, a vacuum flask, or thermos, keeps hot things hot or cold things cold. A vacuum flask, or thermos, does not allow heat transfer by any of the three ways that heat can travel. The silver coating on the inner bottle prevents heat transfer by radiation, and the vacuum between its double wall prevents heat moving by convection. The thinness of the glass walls stops heat entering or leaving the flask by conduction. The case surrounding the flask provides additional insulation.   Previous: Back Book: 1001 Section: Science and Technology Chapter: Heat and Light