ASPECt
Energy: Forms, Transformation, Transfer, and Conservation
Item RG010003: A fan in front of a fireplace will blow warm air across the room to the other end of the room causing the thermal energy of the air at the other end of the room to increase.
The air in the room pictured below is cool. The fire is warming the air near the fireplace, and there is a fan next to the fireplace.
What will happen to the thermal energy of the air at the other end of the room if the fan is turned on and blows warm air across the room?
- The thermal energy of the air at the other end of the room will decrease because the fan will cool the air by making it move faster.
- The thermal energy of the air at the other end of the room will increase because blowing warm air across the room will move warm air to the other end of the room.
- The thermal energy of the air at the other end of the room will increase because energy is radiated directly by the fire to the air on the other end of the room, not because of the fan.
- The thermal energy of the air at the other end of the room will stay the same because fans blow air; they do not transfer energy.
- Distribution of Responses
- Scale Score for Item Difficulty
(200[Easy]-800[Difficult]) - 491
- Students Responding Correctly
| Group | Correct | Total | Percent |
|---|---|---|---|
| Overall | 508 | 1082 | 47% |
| Grades | |||
| 4–5 | N/A | N/A | N/A |
| 6–8 | 306 | 663 | 46% |
| 9–12 | 202 | 419 | 48% |
| Gender | |||
| Male | 255 | 513 | 50% |
| Female | 240 | 543 | 44% |
| Primary Language | |||
| English | 460 | 940 | 49% |
| Other | 39 | 114 | 34% |
- Disciplinary Core Ideas
- PS3.B Energy is spontaneously transferred out of hotter regions or objects and into colder ones.
- NRC Framework
- Heating is another process for transferring energy. Heat transfer occurs when two objects or systems are at different temperatures. Energy moves out of higher temperature objects and into lower temperature ones, cooling the former and heating the latter. This transfer happens in three different ways—by conduction within solids, by the flow of liquid or gas (convection), and by radiation, which can travel across space.