Item EG085002: For two glasses containing the same number of water molecules, the water with molecules that are moving faster has more thermal energy because thermal energy depends on the average speed of the molecules.
A student has two glasses of water. Glass 1 and Glass 2 have the same number of water molecules in them.
If the average speed of the water molecules in Glass 1 is more than the average speed of the water molecules in Glass 2, will the water in both glasses have the same amount of thermal energy? Why or why not?
- Yes, because water has the same amount of thermal energy regardless of how fast the water molecules are moving
- Yes, because thermal energy depends only on the number of molecules, and there are the same number of water molecules in each glass
- No, because thermal energy depends on the average speed of molecules, and the water molecules in Glass 1 are moving faster than the water molecules in Glass 2
- No, because thermal energy depends on how much molecules rub against each other, and the faster moving water molecules in Glass 1 are rubbing against each other more than the slower moving molecules in Glass 2
- Distribution of Responses
- Scale Score for Item Difficulty
(200[Easy]-800[Difficult]) - 496
- Students Responding Correctly
Group | Correct | Total | Percent |
---|---|---|---|
Overall | 3694 | 8399 | 44% |
Grades | |||
4–5 | N/A | N/A | N/A |
6–8 | 1937 | 4700 | 41% |
9–12 | 1757 | 3699 | 47% |
Gender | |||
Male | 1797 | 4117 | 44% |
Female | 1831 | 4125 | 44% |
Primary Language | |||
English | 3239 | 7256 | 45% |
Other | 369 | 936 | 39% |
- Disciplinary Core Ideas
- PS3.A Temperature is a measure of the average kinetic energy of particles of matter. The relationship between the temperature and the total energy of a system depends on the types, states, and amounts of matter present.
- NRC Framework
- Thermal energy is the random motion of particles (whether vibrations in solid matter or molecules or free motion in a gas)...