Question

which of the following is an example of energy transfer by convection? a hair iron becomes hot when plugged in an oven heats air which passes over cookies, baking them a bowl becomes cold when filled with ice cream

Explanation:

• Convection is heat transfer by the movement of fluids (liquids or gases).
• Option A: A hair iron getting hot is conduction (heat through direct contact in a solid) or electrical energy to heat, not convection.
• Option B: An oven heats air (a gas), and the heated air moves over cookies to transfer heat—this is convection.
• Option C: A bowl getting cold from ice cream is conduction (heat transfer between the bowl and ice cream, solids/liquids in contact) or radiation/conductive cooling, not convection.

Answer:

B. An oven heats air which passes over cookies, baking them