Conduction, Convection, Radiation

Question

1 container is metallic and shiny, 1 container is matte black, 1 container is wide, metallic and shiny and 1 container is metallic and covered with wool outside. A student will pour hot water into each of the container. Which container filled with water with be affected by radiation? Which container filled with water will be affected by convection? Which container filled with water will be affected by conduction

Answer 1

Hi Jon,

First you need to know the difference between radiation, conduction, and convection.

Radiation - when the sun or a light hits an object and the object warms up

Conduction - when an object is physically touched by a heart source and warms up.

Convection - when a heat source causes the hot liquid to rises to the top, cools off, and sinks to the bottom.

To my knowledge and based on the information given, NONE of the containers would react to radiation; you don't have a heat source shining on it to warm the cans up. I'm guessing the only one that might be affected by convection would be the one with the wool on it: the water at the bottom would remain mildly warmer than the water at the top because wool would act as an insulator. It is possible a convection current could occur under the right circumstances: the air on the outside of the container is colder than the water inside the container. The water at the top would cool off faster than the water at the bottom. ALL of the containers would be affected the conduction because the hot water would be poured into the metal cans and the hot water would be directly in contact with the can thereby transferring some of the heat to the can up.