Physics·Heat·Gas/Principles and Exploration
Specific heat and temperature — principles and investigation
The reason why the temperature rises differently for each substance even when receiving the same amount of heat is due to specific heat. Compare the energy supplied and the temperature change while adjusting the material, mass, heating output, and heating time. This is an activity to distinguish between the condition that the heating time is the same and the condition that the amount of heat received is the same.
How does it work?
Substances with low specific heat increase their temperature more for the same amount of heat.
Q = mcΔT · Q = output × time
Try this investigation
- It heats water, cooking oil, and iron with the same output and time. Q = output × time. Heat loss is omitted and all supplied heat is used for temperature change.
- Press the standard conditions button, run it, and record each measurement value.
- Change one mass or heating time at a time. Check the inverse relationship between specific heat and temperature rise.
Interpreting your results
If the mass of water is doubled for the same amount of heat, what is the temperature increase?
Since ΔT = Q/(mc), when the mass is doubled, the temperature rise is half.
Assumptions and limitations
The initial temperature is 20 °C and the specific heat is constant. Use 4200 water, 2000 cooking oil, and 450 J/(kg·K) of iron. Heat loss, container heat capacity, and phase change are omitted. Permissible conditions were limited to below the phase change temperature.