The correct answer is option 2, which states that the parts of the graph BC and DE correctly depict the latent heat of the substance.
To understand why option 2 is correct, let`s break down each option:
1) Option 1: AB and BC
- This option suggests that the latent heat is represented by the part AB and BC of the graph.
- However, part AB of the graph represents the initial increase in temperature when heat is applied, which is not related to latent heat.
- Therefore, option 1 is incorrect.
2) Option 2: BC and DE
- This option accurately identifies the parts BC and DE as the representation of the latent heat of the substance.
- In the BC segment, the temperature remains constant even though heat is being continuously supplied. This plateau indicates the phase change occurring, which corresponds to the latent heat.
- In the DE segment, the temperature continues to rise once the substance has completely undergone the phase change.
- Therefore, option 2 is the correct answer.
3) Option 3: CD and DE
- This option suggests that the latent heat is represented by the part CD and DE of the graph.
- However, part CD of the graph represents the gradual