Question

Why it is more hotter for same distance over the top of a candle than it in the side of its flame?

• A. Conduction of heat in air is upward
• B. Heat is maximum radiated in upward direction
• C. Radiation and conduction both contribute in transferring heat upwards
• D. Convection takes more heat in upward direction

Answer 1

The correct option is D Convection takes more heat in upward direction

The hot air is less dense (lighter) than the cooler air around it, so it naturally goes upward, making the area above the flame hotter than the area to the sides of it.

On the side of the fire you’re only getting the radiant heat from the burn. On the top you are getting the convective hot air and actual burn chemicals (smoke, etc.) rising with the less dense air.

Hence the D option is correct .