Isaac wants to make s'mores. He holds a marshmallow on a metal skewer over a fire. A few seconds later, the marshmallow is cooked and the skewer feels warm. What most likely happened?

Question

The fire heated the surrounding air, which cooked the marshmallow.
The heat generated from the marshmallow flowed in the form of thermal energy to the skewer and fire.
The heat from the skewer cooked the marshmallow.
Thermal energy in the form of heat moved from the fire to the skewer and marshmallow.

Answer 1

The most likely explanation for what happened is:

Thermal energy in the form of heat moved from the fire to the skewer and marshmallow.

When Isaac holds the marshmallow over the fire, the heat from the flames transfers to the skewer and then to the marshmallow, causing it to cook. At the same time, the skewer also absorbs heat from the fire, which is why it feels warm.