Which Cup of Water has More Heat Energy?
Explore Intro Page as an interactive EJS simulation for thermal physics.
.png)
1. Watch or Launch
Launch the Interactive
Open the simulation, adjust the controls, and compare what changes on screen before answering the concept-check questions.
2. Big Ideas
What Students Can Learn
- Distinguish temperature from total heat energy.
- Relate water volume to mass when comparing two cups of water.
- Use the model output in kJ to compare heat energy in Cup 1 and Cup 2.
- Connect the simulation to the relationship Q = mcT or, in syllabus form, energy transfer = mass x specific heat capacity x change in temperature.
Guiding Question
Which cup has more heat energy, and is your answer based only on temperature or on both the amount of water and the temperature?
3. Try the Investigation
Predict Before Changing the Sliders
Choose two cups with different water volumes and temperatures. Before reading the heat-energy values, predict which cup has more heat energy and explain whether you are relying on volume, temperature, or both.
Hold Volume Constant
Set both cups to the same volume, then vary only the temperature. Observe which heat-energy value increases and connect the result to temperature as a factor in Q = mcT.
Hold Temperature Constant
Set both cups to the same temperature, then vary only the water volume. Use the kJ labels to show that more water means more mass and therefore more total heat energy.
Challenge the Hotter-Means-More Idea
Create a case where the hotter cup has less water and the cooler cup has more water. Look for a setting where the cooler cup has greater heat energy, then explain why temperature alone is insufficient.
4. Teacher Notes
Lesson Use
Use this as a predict-observe-explain lesson on temperature versus total thermal energy. Begin from the default case where both cups have the same volume, then ask students to predict which cup has more heat energy before reading the kJ labels. Next, keep temperature the same and change only volume so students can see volume acting as mass for the same substance.
Discussion Prompts
Ask: If Cup 1 is hotter, must it always have more heat energy? What evidence from the water height and kJ display supports your answer? What happens when the same temperature is used for a larger volume of water? Which variable did you keep constant, and why does that make the comparison fair?
Teaching Moves
Make students commit to a prediction before moving the sliders, then compare pairs of settings: same volume with different temperatures, same temperature with different volumes, and a small hot sample versus a large cooler sample. This sequence targets the common misconception that temperature alone measures the amount of heat energy.
Model Notes
The source model displays Q = mcT and calculates values using water density, volume, specific heat capacity, and temperature in kelvins. For classroom discussion, distinguish this comparison of thermal energy in the model from the usual heat-transfer form Q = mcΔT, where the change in temperature matters.
5. Concept Check
These questions are generated from the topic and the concept illustrated by the simulation. Use them after students have explored the model.
Concept Score
Correct first attempts build a streak and unlock higher point multipliers on this device.
1. In this two-cup water model, which quantities are changed to compare heat energy?
2. Why can a larger cup of cooler water sometimes have more heat energy than a smaller cup of hotter water?
3. Which equation best matches the relationship illustrated by this simulation?
4. If two cups contain the same volume of water, which cup should have greater heat energy?
5. What misconception does this simulation help challenge?
7. Learning Pulse
Anonymous activity counts show that this resource is being discovered and used.