ASPECt
Energy: Forms, Transformation, Transfer, and Conservation
Item RG151002: Water gives off an increasing amount of energy as its temperature is increasing, and gives off a steady amount of energy when its temperature stays constant.
A student places a lamp near a container of water. He turns on the lamp and then monitors the temperature of the water throughout the day.
At 8:00 a.m., the water in the container is 25°C. At 10:00 a.m., the temperature of the water in the container has increased to 30°C. The water stays at that temperature for the hour. Which of the following statements correctly describes the rate at which energy is given off by the water over this three-hour period?
- The water gives off a steady amount of energy from 8:00 a.m. to 11:00 a.m. because all objects radiate energy at the same rate.
- The water gives off an increasing amount of energy from 8:00 a.m. to 10:00 a.m. as the temperature of the water is increasing, and then gives off a steady amount of energy from 10:00 a.m. to 11:00 a.m. because the temperature stays constant.
- The water does not give off any energy from 8:00 a.m. to 10:00 a.m. even though the temperature is increasing, and then gives off a steady amount of energy from 10:00 a.m. to 11:00 a.m.
- No energy is given off by the water during the three-hour period because it is absorbing energy from the lamp.
- Distribution of Responses
- Scale Score for Item Difficulty
(200[Easy]-800[Difficult]) - 493
- Students Responding Correctly
| Group | Correct | Total | Percent |
|---|---|---|---|
| Overall | 522 | 1150 | 45% |
| Grades | |||
| 4–5 | N/A | N/A | N/A |
| 6–8 | 319 | 685 | 47% |
| 9–12 | 203 | 465 | 44% |
| Gender | |||
| Male | 227 | 506 | 45% |
| Female | 282 | 616 | 46% |
| Primary Language | |||
| English | 454 | 998 | 45% |
| Other | 55 | 123 | 45% |
- Disciplinary Core Ideas
- PS3.B Light also transfers energy from place to place.
PS4.B When light or longer wavelength electromagnetic radiation is absorbed in matter, it is generally converted into thermal energy (heat). Shorter wavelength electromagnetic radiation (ultraviolet, X-rays, gamma rays) can ionize atoms and cause damage to living cells.