Item NG083003: Energy is transferred to the air around hot food as the food cools even though the temperature of the air does not appear to increase.

A cook heats up some food on a stove.  He removes the food from the stove and places it on a plate.  He lets the food cool.  The food has less energy when it is cool.  His friend tells him that some of the energy was transferred to the air around the food.  The cook does not agree with his friend because the temperature of the air around the food did not seem to increase.  Is the friend correct in saying that some of the energy was transferred to the air, and why or why not?

  1. No, the energy could not have been transferred to the air because energy cannot be transferred from one object to another.
  2. No, even though energy can be transferred from one object to another, the energy could not have been transferred to the air because air is not an object.
  3. No, the energy could not have been transferred to the air because all of the energy was used up when the food cooled down.
  4. Yes, even though the temperature of the air did not appear to increase, some of the energy could have been transferred to the air because energy is always conserved.  The increase in the air’s energy is just difficult to detect.

Distribution of Responses

Chart showing distrubtion of responses for Item NG083003

Percent of students responding correctly

Overall56%
Grades 6–853%
Grades 9–1259%
Male54%
Female57%
Primary Language is English56%
Primary Language is not English48%

View data table