Fungus gnats are small, dark, short-lived gnats, of the families Sciaridae, Diadocidiidae, Ditomyiidae, Keroplatidae, Bolitophilidae, and Mycetophilidae (order Diptera); they are sometimes placed in the superfamily Mycetophiloidea. The larvae feed on plant roots and fungi, helping in the decomposition of organic matter.
In each of these situations, you experienced the work of the three types of heat transfer: conduction, convection, and radiation. Conduction, or direct heat, occurs when the faster moving molecules of the fire collide with the cooler molecules of the marshmallow, causing them to move faster and become hot.
HEAT CONDUCTION. When a temperature gradient exist in a material, heat flows from the high temperature region to the low. temperature region. The heat transfer mechanism is referred to as conduction and the heat transfer rate has been. found to be proportional to the temperature gradient normal to the heat transfer surface. For a 1-dimensional.