Question

you sit with friends around a campfire, roasting marshmallows. which transfer of thermal energy involved in this system is an example of radiation?

a. thermal energy moves from the marshmallow to your fingers as you touch the marshmallow.

b. thermal energy moves through the air from the flames to the marshmallow.

c. thermal energy moves from the outside of the marshmallow to the inside of the marshmallow.

d. thermal energy moves within the air above the flames as warmer air rises.

Explanation:

To solve this, we analyze each option based on heat transfer methods (conduction, convection, radiation):

• Option A: Touching the marshmallow involves direct contact, so this is conduction (heat transfer through direct contact), not radiation.
• Option B: Thermal energy from the flames to the marshmallow through air without a medium (other than electromagnetic waves) is radiation. Radiation is heat transfer via electromagnetic waves, and flames emit heat via radiation that travels through air to the marshmallow.
• Option C: Heat moving from the outside to the inside of the marshmallow is conduction within the marshmallow (heat transfer through a material), not radiation.
• Option D: Warm air rising and transferring heat is convection (heat transfer via fluid movement), not radiation.

Answer:

B. Thermal energy moves through the air from the flames to the marshmallow.