The graph given below indicates change in temperature (0) when heat (Q) was given to a substance. Which among the following parts of the graph correctly depict the latent heat of the substance?

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Q: 55 (NDA-I/2012)
The graph given below indicates change in temperature (0) when heat (Q) was given to a substance. Which among the following parts of the graph correctly depict the latent heat of the substance?

question_subject: 

Science

question_exam: 

NDA-I

stats: 

0,3,4,0,3,2,2

keywords: 

{'latent heat': [0, 0, 1, 3], 'graph': [0, 1, 1, 0], 'temperature': [0, 1, 1, 7], 'heat': [10, 3, 13, 46], 'ab': [0, 0, 1, 0], 'bc': [1, 0, 1, 2]}

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