Thermodynamics — Class 11 Physics NCERT Solutions (Free)
Free step-by-step NCERT solutions for Class 11 Physics chapter "Thermodynamics" — 8 important questions with detailed answers for CBSE board exam preparation.
TL;DR: Free step-by-step NCERT solutions for Class 11 Physics chapter "Thermodynamics" — 8 important questions with detailed answers for CBSE board exam prep…
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Key Questions Covered:
- An ideal gas undergoes isothermal expansion from volume 1 L to 2 L at 300 K a…
- Calculate the work done on an ideal gas when it is compressed from 4 L to 1 L…
- One mole of an ideal gas at standard temperature and pressure (STP) undergoes…
- + 5 more questions in the full chapter
Solutions Summary:
| Question | Status |
|---|---|
| An ideal gas undergoes isothermal expansion from volume 1… | ✓ Solved |
| Calculate the work done on an ideal gas when it is compre… | ✓ Solved |
| One mole of an ideal gas at standard temperature and pres… | ✓ Solved |
Showing 3 of 8 questions
Q1: An ideal gas undergoes isothermal expansion from volume 1 L to 2 L at 300 K against a constant external pressure of 2 atm. Calculate the work done by the gas. (1 L·atm = 101.3 J)
Step 1: For isothermal expansion against constant external pressure:
W = P_ext × ΔV
Step 2: Calculate change in volume:
ΔV = V_f - V_i = 2 - 1 = 1 L
Step 3: Calculate work:
W = 2 atm × 1 L = 2 L·atm
Step 4: Convert to Joules:
W = 2 × 101.3 = 202.6 J
Alternatively, using W = nRT ln(V_f/V_i):
For ...
Q2: Calculate the work done on an ideal gas when it is compressed from 4 L to 1 L at a constant pressure of 2 atm. (1 L·atm = 101.3 J)
Step 1: For compression at constant pressure (isobaric process):
W = P × ΔV = P × (V_f - V_i)
Step 2: Since volume decreases (compression), ΔV is negative:
ΔV = V_f - V_i = 1 - 4 = -3 L
Step 3: Calculate work done ON the gas:
W = 2 atm × (-3 L) = -6 L·atm
Step 4: Negative sign indicates work done...
Q3: One mole of an ideal gas at standard temperature and pressure (STP) undergoes adiabatic expansion to 10 times its original volume. If γ = 1.4, calculate the final temperature.
Step 1: For adiabatic process: TV^(γ-1) = constant
T₁V₁^(γ-1) = T₂V₂^(γ-1)
Step 2: Rearrange for T₂:
T₂ = T₁ × (V₁/V₂)^(γ-1)
Step 3: Substitute values:
T₁ = 273 K (at STP)
V₂/V₁ = 10, so V₁/V₂ = 0.1
γ = 1.4, so γ - 1 = 0.4
T₂ = 273 × (0.1)^0.4
Step 4: Calculate (0.1)^0.4:
(0.1)^0.4 = (10⁻¹)^0.4 ...
Showing 3 of 8 questions. Visit the full page for complete solutions.