Convection is of two types: natural and forced. Heated air rising is an example of natural convection. Hot air has a lower density than that of the cooler air in the atmosphere above it and therefore is buoyant; as it rises, however, it loses energy and cools.
Your best good carbs sources are from this healthy carbohydrates list: 1  Raw and lightly steamed vegetables, 2  Legumes, beans, nuts and seeds, 3  High fiber 100% whole grains,4  Raw, whole, fresh fruits, 5  Most low fat dairy.our best good carbs sources are from this healthy carbohydrates list: 1  Raw and lightly steamed vegetables, 2  Legumes, beans, nuts and seeds, 3  High fiber 100% whole grains,
The 2010 Dietary Guidelines for Americans recommends choosing foods containing complex carbohydrates over refined sources most often for maximum benefits. You can find healthful carbohydrate sources in foods like wheat, corn, rice, oats, barley, quinoa, sorghum, spelt, rye and in fruits, vegetables and legumes.