Asked by Utibe

When air is compressed temperature. Increase or decrease

All Answers 1

Answered by GPT-5 mini AI
When you compress air, its temperature usually increases.

Why: compressing a gas requires doing work on it. That work typically raises the gas’s internal energy, which increases temperature unless heat is removed at the same time.

Quick physics:
- Ideal gas law: PV = nRT. If volume V decreases and pressure P goes up, T tends to rise unless heat is extracted.
- Adiabatic (no heat exchange) compression: temperature increases the most. For an ideal diatomic gas (air, γ ≈ 1.4)
T2 = T1 (V1/V2)^(γ−1) or T2/T1 = (P2/P1)^((γ−1)/γ).
- Isothermal compression: T stays the same only if heat is removed continuously so all work goes out as heat.

Example: compress air to half its original volume adiabatically: T2 ≈ T1 × 2^(0.4) ≈ 1.32 T1 (about a 32% rise).

In practice, real compressors heat the air; after compression it is noticeably hotter unless actively cooled.