# Mechanical Engineering - Thermodynamics - Discussion

Discussion Forum : Thermodynamics - Section 4 (Q.No. 3)
3.
When the gas is cooled at constant pressure,
its temperature increases but volume decreases
its volume increases but temperature decreases
both temperature and volume increases
both temperature and volume decreases
Explanation:
No answer description is available. Let's discuss.
Discussion:
8 comments Page 1 of 1.

Amit said:   4 years ago
Yes, @karthick, but here the condition is given of isobaric cooling so D option is correct.

Aish. said:   5 years ago
Yes, I agree @Karthick Ravi.

Karthick Ravi said:   6 years ago
When gas get cooled it starts expanding hence volume increases.

Sanjay gandhi said:   6 years ago
Based on Charles's law.
P=Constant.
V/T.

Chahat sharma said:   7 years ago
PV=RT
P=constant.

Therefore, when gas is cooled so temperature decreases so eventually volume will also decrease since direct relationship exists.
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Kavi said:   7 years ago
But cooling is also temperature reduction process, law is not only for the increase in temperature @Mubashir.

Mubashir said:   8 years ago
Yes @Manoj. But when gas is heated at constant pressure. Right answer is D because here is "cooled" word.

Manoj said:   10 years ago
By charles law.

At constant pressure volume is directly proportional to temperature.
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