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,
Carbohydrates are found in many foods in different forms: sugars, starches, and fiber. Your body requires all three forms at different times. For example, during long periods of exercise (lasting more than 1 hour), sugars are the best source of fuel-they are used quickly by the body when your body needs energy most. You may have heard that potatoes and bananas should be avoided. 2  But in reality, these are considered good carbs. 3  It's just a matter of making sure that you are consuming an appropriate portion  a small-medium sized banana, and 1/2 to 1 cup of potatoes (depending on your size and meal composition) is a healthy choice.