Energy is transferred from atom to atom along the bar. At the hot end, the atoms are vibrating a lot. As they bump into each other, the energy is passed along the bar. Heat Transfer For heat to flow from A to B, A must be at a higher temperature than B. Heat energy causes gas and liquid molecules to move around faster, and causes particles in solids to vibrate more rapidly. When particles move faster it shows up as a rise in temperature. This extra kinetic energy in the particles tends to get dissipated to the surroundings. In other words the heat energy tends to flow away from a hotter object to its cooler surroundings.
If there’s a difference in temperature between two places then heat will flow between them. Conduction Is the transfer of energy (heat) between materials in contact it happens mostly in solids, but also a little in liquids. As part of substances is heated the particles inside it vibrate. These vibrations are passed from particle to particle. Without the material or the substance moving. Convection happens in liquids and gases it is the transfer of energy (heat) by the movement of a liquid or a gas due to differences in density. Water is heated and Water cools, Becomes less dense becomes more
And rises. Dense and sinks. Convection current is set up which carries heat around the beaker. Radiation Is the transfer of energy (heat) from one place to another by means of electromagnetic waves. Every object radiates infrared radiation; black matt surfaces are best at absorbing and emitting this. White, silvery, shiny surfaces are the worst absorbers and emitters Radiation travels through anything see-through including a vacuum. E. g. Tin foil would stop radiation. Evaporation In a liquid the hottest particles are moving the Fastest, fast moving particles near the liquid
Surface are likely to break free of the liquid and Evaporate. Only the fastest particles will achieve this, leaving the slower “cooler” particles behind. This lowers the average energy of the particles left in the liquid and so the liquid as a whole becomes cooler. It then takes in heat from its surroundings and thereby cools whatever its in contact with. What am I trying to find out? I am trying to find out what insulator is best at keeping the most heat in. I will try out lots of different insulators such as cloth, newspaper, a lid, none and bubble wrap to see what will happen.
I am trying to find out if this makes a difference to how quickly it cools down if I was to use newspaper wrapped round it or a lid on top or if it doesn’t even matter. Prediction I think that the can that will keep the most heat in will be the can with newspaper round and I think the can without any insulation will loose the most heat due to radiation because this looses heat through the sides, I also think the can with the cardboard lid on top will keep quite a bit of heat in because there will be no convection.
The can with bubble wrap around has air bubbles and air is a good insulator but I don’t think this will keep the most air in. Method I am going to use five copper cans of the same size and wrap one in newspaper, one with nothing, one with a cardboard lid on top one with bubble wrap and then one with cloth. I will then fill each can up with a 100ml of boiling water. We will then time each one using a stopwatch for fifteen minutes taking the temperature using a thermometer for every three minutes We will record the temperature in i?? C.